Select the most important 2-3 ideas related to your topic. Put the word AND between each new word or idea; this tells the database to look for resources with ALL your terms.
diabetes type 2 AND diet
Use quotation marks ( " " ) around phrases (two or more words).
"coronary artery disease" AND angioplasty
Use the asterisk (*) to truncate a word; this tells the database to look for all words that have the same base. In the example below, search results would include treat, treats, treated, treating, treatment, etc.
diabetes AND treat*