No, I think "effectively useless" is the correct description. The search facility returns posts which have any of the words you are searching for. You can not specify that you want all the words, so as you have found out you get many irrelevant results.
Originally Posted by srm
Apparently it is set up this way as it minimises the overheads on the servers, presumably because as soon as it hits one of the words you are searching for, it can stop searching the rest of the thread.
The technical name for this is a primal-dual interior-point search algorithm (also know as a shift half interior term search, or S.H.I.T. search).
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