Computers cannot understand language so it's important to give them simple and logical instructions. There are four basic techniques you can use to improve your search skills: keyword searching, Boolean expressions, phrase searching, and truncation. All of these techniques can be combined together to create precise or broad searches.
Most of us are familiar with keyword searches: you enter in words and you get back results which contain those words. It's important to choose your keywords carefully otherwise you will get no results or the wrong results.
Use these basic tips to improve your keywords:
To search for a phrase or multi-word concept place the words or phrase in quotation marks. The quotation marks tell the search to find all of these words together in this order.
Example searches:
Truncation is a way to place "wildcard" characters in your searches. This is useful when trying to include word variations in your searches. You need to be careful where you truncate a word - if you truncate too early you may end up with unexpected results that contain unrelated words with the same spellings. The asterisk(*) is the symbol most indexes use for truncation.
Example good truncation search: bacteri*
Example bad truncation search: gam*
Boolean searching is a way to tell the computer to do certain things with keywords that you are using in your search.
When you combine keywords with AND you will only get results which contain all of the keywords joined by AND.
Use AND when you need to narrow a search to contain ALL keywords.
Example search: cat AND dog
When you combine terms with OR you will get results which contain any of the terms joined by OR.
Use when you want to broaden a search to search for related terms or variant spellings (example: "climate OR climatic OR climates")
Example search: cat OR dog
NOT is used to specify keywords to ignore. Some search engines and databases don't support NOT (Google uses "-" instead for example). NOT can be useful when you are searching for a word with multiple meanings or need to exclude certain topics from a search.
Example search: cat NOT dog
You can combine multiple search techniques and if you have a complex search you can use parentheses to group different sets of instructions:
Example searches: (cat OR cats) AND train*