Advanced Search opens up a world of new possibilities. You have options to search for exact phrases, you can choose to exclude certain words, or you can search for a ranges of numbers. Then you can filter your search results further by language, region of publication, or date of the last update. There is even an option to filter content by reading level, which works to some degree, though not perfectly since reading levels are a topic of great debate.
There are other options in Advanced Search as well, all of which should help you to find the perfect site, PDF, video, or document to complete your research. Just like any computer, Google Search is only as effective as its user. Google is unable to read your mind, though they’re working on that. Until then, try Advanced Search.