Databases are set up to do keyword searches. What is a keyword? Technically speaking, it’s any string of letters that you type into the search box, which the database then attempts to find anywhere in any of its records. The database can’t understand English, so it just matches strings of letters. There are specific “operators” you can use to make keyword searching more effective.
Say I want to search for swine flu. If I just type that in, I will get all the results that mention swine one place in the article, and flu some other place in the article. Not all of them will be relevant. The solution for that is to put quotes around phrases so that they are searched as a unit and not separately:
Another thing is that if I’m looking for articles about swine flu and type that in, I will not get any results that call it H1N1 instead. The solution is to think up as many synonyms for your concept as possible. Join all the synonyms for a concept with OR, and put them inside a pair of parentheses.
Say I want to research the correlation between people getting swine flu/H1N1 and having respiratory complications. Those are two separate concepts, each with their own keywords. Put each concept in parentheses like before and then join the two concepts with AND.
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