When you pick your topic, it's not set in stone. Picking and adjusting your topic is an integral part of the research process!

The first step in choosing keywords is to think about what information you need to search for. This seems obvious, and to a certain extent you are probably already doing it. But a more systematic approach will reward you.

1. Break the search down into the key concepts/ideas.  For example, if we are looking for information about nutrition and cancer the main concepts are nutrition and cancer
2. Brainstorm (or look for in your background reading) synonyms since not all authors or websites will use the same words or terminology.  Making a concept box can greatly aid you in your search.

Too Many Results?

1. Did you combine with OR rather than AND? Remember to combine similar terms with OR
   (e.g. SARS OR severe acute respiratory syndrome and different terms with AND (e.g. SARS AND vaccines)
2. Is there a more specific term or phrase you can use?
   e.g. SARS instead of infectious disease?
3. Is there another word or phrase you can add? The more words you AND together, the more focused your results.
   e.g. SARS AND vaccines AND human
4. Can you limit your search words/terms to the title or subject/descriptor fields? This makes for a more precise search.
5. Can you limit your search by publication year or language?
    

Too Few Results?

1. Did you combine all your words with AND? Remember to combine similar terms with OR
   e.g. SARS OR severe acute respiratoty syndrome
2. Use a wildcard (*) to retrieve different word endings (plural vs. singular, Canadian vs. American spelling).
   e.g. vaccin* to find vaccine, vaccines, vaccination, etc.
3. Consider using more broad terms.
   e.g. infectious diseases instead of SARS
4. Remove limits such as publication year.
5. Try another journal article database.
6. Look for references cited in the articles you find