Before you start searching, think about keywords for your given subject. You may find it useful to do some preliminary reading in textbooks and encyclopaedias, which will help you identify some keywords, and perhaps also key authors.
A good way to create a search strategy is to search for the keywords of each concept separately and then combine the results to narrow down your topic. This is called using Boolean operators.
| Function/Operator | Example |
|---|---|
| AND | heart AND surgery – finds items containing both the words heart and surgery. Use to combine concepts |
| OR | heart OR cardiac - finds items containing any of the following: the word heart, the word cardiac or both words (includes singular and plural, US and UK spelling variations). Use for all the terms that mean the same concept. |
| ANDNOT | (use sparingly) Searches for articles that do not contain the following words e.g. heart ANDNOT surgery |
If you are doing a simple search then you can write the Boolean into the search box. Take care that you have spelled everything correctly. E.g.
For longer searches it is better to use the search history to combine. Search for individual words or phrases. Then click on Search at the top of the results page to search for others. As you do this, the terms that you have searched for will appear at the bottom of the search page.
Then to combine your terms, click each row that you would like to use and then click on Combine queries at the top of your search history. You will then get this box where you can choose which Boolean operator you want to use. In the below image, I’m combining heart OR cardiac.
If you would like extra information about searching please take a look at the Medicine Literature Search Tutorial. Although written for medical students, it has information that students of all disciplines will find useful. This includes sections about having a focused research question and searching databases with keywords.