Okay, it has been a while since I took Latin. I recall that the verb "captare" (conjugated here as captamus, first person plural) can mean "to grab", and it can mean "to try, to aim at." But to insist that "we try to grab" is the only correct answer for "captamus" and reject "we grab" can't be right.
captō -> I strive to seize, catch or grasp at.
You may be thinking of capiō (capere) which is 'to capture, seize, etc.'.
No you're quite correct, Captare means to try for, strive for etc., as well as simply to catch (L&S s.v. capto). This sentence could mean "we seek the mouse" "we try to catch the mouse" or "we catch the mouse", I'm finding the lack of flexibility in the Latin beta a little frustrating so far :)