Basic retrieval techniques increase the efficiency of your searches
You need some basic retrieval skills when seeking information from organized databases. Most databases do not work like Google which corrects typing errors, automatically uses the synonyms of search words, and arranges search results so that the most relevant results are listed first. Have you noticed that you can narrow searches also when using search engines such as Google?
Search techniques gain power on results. Check out four techniques below before entering your search words into the database. By utilizing them, you can get the results as relevant as possible. Please note that you should, nevertheless, always check the instructions of the database you are using. It is, for instance, useful to check the database specific truncation character before beginning your search.
Information retrieval techniques
Combine keywords
Searching with one keyword easily brings unrelated search results. It is worth combining the keywords into a search query. It happens with AND-OR- and NOT (Boolean operators).
AND refine your search
- When you want the search result to have all the searched words.
- Search Coffee AND Health brings results in which both words coffee and health occur.
OR extends search
- When you want to have any of the words in the search result.
- The search for coffee OR caffeine yields results with either of the words coffee or caffeine.
NOT limit your search
- When you want the first word to appear in the search result, but the second does not.
- Search Coffee NOT History searches for all results where the word coffee appears, but excludes any history from the search results.
The search can use many operators (AND, OR, NOT) at the same time. In the picture below, open combining search words (Boolean logic) is explained.
(picture: Terhi Kaipainen, CC BY-SA 4.0.)
If only one search field is used, parenthesis characters are added to tell the database the order of the search. Databases recognize and interpret information within parentheses first.
When you type in ((tomato OR cheese) AND hamburger), the database search engine retrieves results containing the word tomato or the word cheese together with the word hamburger in the fields searched by default.
What do searches look like in databases?
In advanced searches in most databases, AND-OR and NOT operators are ready to be selected between search fields. They can also be typed between search words.
Truncation broadens your search to include various word endings (or beginings in some databases). To use truncation, enter the root of a word and put the truncation character at the end.
(Picture: Terhi Kaipainen, CC BY-SA 4.0.)
In addition to the truncation character, you can also use wildcards, which substitute one letter of a word. So, similar to truncation, you can broaden your search to include various word spellings with wildcards. You can e.g. search the terms test and text at the same time by substituting one letter with a wildcard: te?t .
Always check the truncation character and wildcard from the instructions of a database. Usually the truncation character is an asterisk * and the wildcard a question mark ?, but there are exceptions. In some databases, terms are truncated automatically, so there is no need for truncation characters.
Use a phrase search for multipartition keywords
You should use a phrase search when a keyword consists of two or more words that you want to be in the order and format written in the search result. Enclose search terms with double quotation marks (i.e."global warming") and the search engine looks for words in the exact order in any field in the metadata and full text (when applicable). As long as the search engine finds just one instance of the words in exact order, the record is included in the result list.
Under is an example of a phrase search done in Kaakkuri. For example, in the search “social media” the words social and media sequentially appear in the search result. Without quotation marks, search words can be far apart, increasing the number of irrelevant search results.
Narrow the search
You can narrow your search in many different ways. The most common ways to narrow the search are:
- language,
- publication date,
- publication type (e.g. book, e-book, article, thesis),
- keywords (search terms).
In most cases, it is also possible to narrow only those materials that can be read immediately (e.g. full text/free full text or available online). However, most of the articles can be read through other ways. Please contact Library Services if the material you need does not open.
In many databases, it is possible to narrow down only peer reviewed articles to the search result.
In Kaakkuri, you can narrow your search with the advanced search or by applying the narrowing options shown on the right side of the screen after you have made a search.
Target the search
The search can be targeted to a specific section of the search result, for example, only the words that appear in the title. In this case, the searched words must therefore appear in the title of the search result.
For example, in Kaakkuri, the search can be directed to a title, author, or subject from the drop-down menu. The default option is “all fields”, in which case the search targets all searchable data.
Building search strings
You can search for information using single search terms, truncated search terms, and
combinations of search terms (AND, OR, NOT) and by limiting searches.
Next you can combine the above-mentioned search techniques into search strings. Search strings are used when you want to include several search concepts and several search terms describing the same concept in one and the same search. Search strings are also used to search for information in a literature review.
Example of a search string
("young people" OR adolesc* OR "high school students") AND ("exercise habits" OR "physical activity")
Search tips
Video: Clark, Sarah 2016. Online Research: Tips for Effective Search Strategies (CC-BY 4.0).
Evaluating the search results
It is useful to evaluate the search results, so that you can alter you search strategy, if needed. For instance, you might need to change your search terms, search strategy, or search phrase and its formulation.
| Too many search results | Too few search results |
| Use subject headings instead of keywords. | Use more general terms to broaden the search. |
| Check your use of the truncation character. Did you truncate the search term too early? | Check your use of the truncation character. Are all inflections of the search term included in the search? |
| Reduce the amount of variants and synyonyms of the search term. | Use more variants and synonyms by applying the OR operator. |
| Use more AND and NOT operators. | Reduce the amount of AND and NOT operators. |
| Add more narrowing operators. | Reduce the amount of narrowing operators. |
| Is the database you are searching appropriate for your topic? Have you typed the search terms correctly? |