lucy24 - 1:34 am on Aug 11, 2012 (gmt 0)
Same domain is bad enough. I've done searches where the first three results are all the same page-- by amazing coincidence, Amazon. Just different versions of the same book.
There's a thread somewhere hereabouts concerning the equally unpredictable - sign. Even if it works as intended, it may not, uh, work as intended. Search for "widgets -foobar" and you've excluded all the pages that helpfully say "widgets often come up in the popular phrase 'foobar widgets'. But I'm here to talk about widgets in their own right".