Some searchers turn on case sensitivity if you use capitalisation anywhere in your string. For real search power, you have to get into Boolean logic, named after its inventor, 19th century Irish mathematician George Boole. The standard Boolean operators are AND, OR, NOT or NEAR, and between them they let you focus a search very finely. They group terms and operators together so other operators can deal with the bracketed section as a whole. Nested brackets are allowed, and should be handled properly by any competently written engine.
Different engines have their own shortcuts for and extensions to the Boolean operators.
Every search engine that supports non-obvious search modifiers like Boolean operations should have these modifiers explained in the help file. Many engines have basic and advanced interfaces, so people doing simple searches aren't intimidated by extra features. Check the help pages. Extra features unavailable from the meta-searchers, like matching files of a particular kind or pages in a particular date range, can help winnow out valuable information in those annoying situations when you know what you're after but can't quite put it into words. Where to search Now that you know how to look for things, let's get into where you should be looking.