The reverse image search will help you find related images (including other sizes of the picture, sites that include the image, and similar images) on the web:
1. In Google, select Images from the choices below the search bar.
2. Click the camera icon that will appear on the search bar.
3. Choose to either give a URL (web address) for an image, or upload an image - the image itself will be your search term!
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.