There are now hundreds of search engines and you need to be able to recognize they type of search engines you encounter.
There are:
Major search engines include the most popular or important services from all over the world. They are generally commercial sites that are very well-maintained, and many will contain both search engines and directories you can browse.
Paid listings search engines where listings are bought and sold (e.g., companies pay to be high on the return search list).
Reward search engines offer cash, prizes, or other goodies to those who use them.
News search engines search for the latest news stories from carefully selected media information sources on the Web. These services can provide exceptionally good results for current event searching because they will spider only the news sites once or twice a day. Thus, the results are unusually focused and up-to-date.
Specialty search engines are available to help you find more than just Web pages and Web sites. Here are search engines that will search through specialized search engines, newsgroups, directories, specialized search databases, mailing lists, software catalogs, and more.
Kids search engines are usually more like “safe havens,” directories maintained by people who carefully select sites to serve the beneficial interests of children. They cover things that kids really enjoy and they carefully exclude sites that parents and teachers might find inappropriate for kids, such as those that deal with explicit sexual matters, pornography, violence, hate speech, gambling, and drug use.
Metacrawlers allow searches to be sent to several search engines all at once. The results are then combined and returned on one or more pages for convenient viewing, with duplicates eliminated, ranked in order of importance, or by relevance, with regard to your search string.
Desktop search utilities are software programs that let you search the Internet or a cloud enabled storage system from your desktop.
Search engines come is all shapes and sizes. They act as the gatekeepers to knowledge developed and even curated by individuals, schools, colleges, and universities, non-profit, social and professional organizations, government agencies and media of all types.
Learn the differences. Know what they are capable of doing.