That is completely intentional; it does "substring" matches, as I said. Note that it also matches "PerlIde4.2" when you search for "ide" and "compiling", "compiler", and "compiled" when you search for "compil". In my experience, in such a simple interface where you can only offer one or the other, the substring behavior is much preferable (especially when searching titles).
You'll have more control with the next "Super Search".
Update: I just experimented with a change where searching for ide searches for both "ide" and " ide " which means that a node title containing " ide " gets 2 points while one that only contains something like "side" only gets 1 point. Of course, that prevents the nodes containing "editor/ide" from showing up and I'm not about to go back to regular expressions for simple search nor try to determine what a good "word boundary" is and then document all of that complexity just for the simple search. But with the addition of a "search more" option in Search results, this modification might be used.
And it gives me some ideas for "Super Search". Thanks!
(but my friends call me "Tye")