Dear ANet,
Please understand that when I type more search terms I expect to get fewer results. The point of specifying multiple terms is to narrow down the results. That is how search engines work.
For instance when I type “worn scale” I expect to get Worn Scale Coat, Worn Scale Boots, Worn Scale Helm, etc. I.e. the stuff that has both terms in it. Instead I get everything with either “worn” or “scale” in its name. That is not a particularly useful search, which becomes practically useless search if I try to sort the results.
This is obviously by no means a game breaking issue, but for someone who implemented this type of functionality many times before, this looks very unprofessional.