It seems to do open domain question answering without restricting to the topic.
> Is the word cat made of 4 or 5 letters?
>> The word cat is made of 4 letters, 3 of which are in the stem.
> Is the word cat made of 4 or 5 letters?
>> The word cat is made of 4 letters, 3 of which are in the stem.
Adding specific product documentation would give it "domain expertise" of sorts (assuming this is what OP did), but training it ONLY on your documentation -- I don't know enough to call it, but my intuition is that it would weaken it's ability to interpret the users' questions.