Keywords: As in academic databases, when you're deciding what words to put in the search box, try to choose words that are likely to appear on the result you're looking for. For example, instead of saying my head hurts, say headache, because that’s the word a medical site would use.
Search Shortcuts: Google searching is familiar to most of us, but you can make Google work harder for you by applying these helpful search bar tricks* alongside your keywords -- of course, the library databases provide you with much more sophisticated search engines, which allow for even more search shortcuts. Get tips for academic database searching in your subject's LibGuide.
*below are screen shots from the Google help files as of November 2015. Google changes a lot, so keep up to date here.