I have a Node with a two letter Name "HR" which is short for Human Resources. When I search for it in Bloom, Bloom refuses to expand and complete it, even though it's an exact match.
I'm guessing that you have to type at least 3 characters before Bloom gives you a hint. This makes some sense, as the user would get an unhelpful huge list of possible matches after typing one or two letters.
I think you should allow 1 or 2 character searches to complete IF it's an exact match.