they chose to use some specific, static operators so that you can do interesting things with the data, instead of having it simplify your request to what you "probably" want.
I understand your point: and I would have figured it out. But this is marketed as an everydfay search engine - which it's not, it's an advanced search for an encyclopedia :)
i imagine if it turns out to be a common problem, they'll probably give you a little reminder message about it. "if you're looking for data comparison, use vs. instead of /"