Qiana W cant use under aoe and buff grabs

So i seen that at times when i was using her W that i cannot use it under the enemy turrets and any other aoe things like sona's abilities etc, i may just be delusional but at time i have to basically search for an open spot to use my W at times which is pretty annoying when you cant just aim at something and W, you gotta go and search for it. Also i seen that when aiming at the ground while a bush is nearby seems to grab the bush buff instead of the ground buff at times if you are too close to it but still on the ground.