3. Read the instructions.
No two search engines work exactly the same way, so it pays to read the online help and search tips provided at the site. For example, some search engines default to doing an AND search--type several words in the search box and the engine will assume you want to find all of them in your search results. Other search engines take the same request and by default perform an OR search--returning pages that contain any one of the words but not necessarily all of them.
At a minimum, you need to learn how to do AND, OR, and phrase searches at any site you're going to use on a regular basis. Another important point to zero in on is case-sensitivity--whether the search engine recognizes and acts upon uppercase and lowercase letters in your search request. Some search engines offer case-sensitive searching, others ignore case completely.