This type of search would be completely useless for inexperienced users but indispensable to experts. A search tool aimed at a wide audience should be both flexible in its input and economical in its results. It is surprising how many Web sites still employ search boxes that accept only a single keyword. For users to get the most out of a search engine, they need to understand what it can and can't do. I've often seen users complain that a certain search feature is unavailable, when the feature actually has been implemented.
Every search box needs a prominently displayed explanation, or link, that says exactly what it does.
Jody Dodson is executive vice president of cPulse, a developer of customer service applications for Internet businesses.