Keywords are words that can appear anywhere in an article including the title or the article text. You'll use keywords to search all of the library databases.
Before you begin searching, try to think of the keywords and related terms that best describe and relate to your topic. For example, if you were researching depression in new moms, you might come up with this list: postpartum, mothers, infants, depression, baby blues, PPD, postpartum depression, babies, postnatal, after birth, moms, and newborns.
When it comes to searching academic databases, use scientific language. For instance, search mothers instead of moms. Another example might be looking for children instead of kids.