Switching your search engines.(on the net)

For many information needs, a simple search at any Web search engine will find at least a few pages with the desired answers. Sticking with just one search engine--whether it is Google, Yahoo!, Live, or Ask--can work well as long as that search engine answers all queries. It is when the search favorite fails to deliver or when comprehensive results are desired that the differences between the search engines' underlying databases make it necessary to use several of them.

While many Web wanderers think that Google is comprehensive, and Google itself claims the lofty aim of organizing the world's information, many information nuggets remain excluded. When searching for unusual topics and unique pieces of knowledge, the overlap among the tendrils of the indexed Web continues to be vastly smaller than many people expect. One useful tactic: Switch from one search engine to another to cover the Internet more broadly.

WHEN TO USE

Over the last year or so, I have been documenting cases where only one or two search engines had the answer I sought. With most of these, the result was not found by Google. Any time that the first search engine gives zero or relatively few results when running a general Web search is a good reason to search the others. There are times when no search engine will find an answer. But on a fair number of occasions, one of the search engines did have the answer, although it was not necessarily the first one I used.

Are you searching for email address, instant message handles, a citation, or other unique text strings? Be sure to check several search engines. Search engines cache copies of pages on different dates, so looking for a cached page from a specific date is another reason to look under multiple rocks. For breaking local news stories, which news source will post something first? Will it be a blog or a news site? Try several blog and…