A lot of search techniques depend on the search engine or database you are searching in. Some of them, however, are quite universal, and can make your search a lot more efficient with just the slightest bit more effort.
Most search techniques are aimed at refining or manipulating your search results. This is either possible by setting limits (such as date, publication type, language) or by manipulating your search terms using operators. The various ways can be classified in two categories: