That makes complete sense -- a "whole word" sort of motifier. Though, in 6.11 if I search for "ant" I got 22 documents highlighting the word "QUANTITY". If I threw asterisks on either side of "ant" I got over 200 hits, also finding the word "ATTRACTANT". I am not sure I understand why a straight "ant" found inside QUANTITY would not also be found in ATTRACTANT. A "contains" should be a contains whether a search term is found at the start, middle, or end of a word.
Definitely differing results, though!
The "?" makes complete sense, though -- that is a good example you offer.