Define your research question or topic (Why? Understanding your topic before you dive into searching databases keeps you focused on your topic and less likely to get sidetracked by irrelevant material.) EXAMPLE: What is the impact of air quality on children with asthma?
Break it down - Pick out the core concepts (usually noun or noun phrases) (Tip: You want between 2-4 keywords. Avoid fluff words like impact and effect. Why? Words such as impact are used all the time so you are more likely to get results that aren't relevant to your topic.) EXAMPLE: air quality, children, asthma
Identify 1 or 2 synonyms for each core concept (Why? Computers aren't that smart. They won't do any interpretations for you, which means they will spit out only what you put in.) EXAMPLE: air quality = pollution ; children = youth, adolescents ; asthma = "bronchial asthma"