Keywords make the query more effective. Here are some tips:
1) Think about the key ideas of the query. Only type in what you are looking for, no extras.
2) Choose words that you think would appear on the page that is the perfect answer for you.
3) Pretend to be the author of that page -- what would you type / include?
4) Keep query short, on-topic, & composed only of words you might find on the perfect results page.
5) Every word in your query matters.
6) Word order can influence search. [black and white] does not equal [white and black].
7) You can search for quotes even if you have forgotten a word. Typing "do not go * into that good night" will retrieve information about the Dylan Thomas poem, "Do Not Go Gentle Into That Good Night."
8) When you log into Google and do a search, Google remembers who you are. Click on the globe button at the top right of your search results to "depersonalize them."
Adapted from the Google Online Course, "Power Searching With Google"