Very good game but also frustration

This game is excellent but there is some frustration
I'm only in this game hard because not being a beginner FPS.
When I covered the corner of a wall or behind a box or any other, without being completely covered, I try to take down a terrorist with a funny feeling he is behind bulletproof glass so to have it I must still shifts me as I saw him very well, sometimes the terrorists do not even see me
The worst is during the 3rd China Sea on a mission
On the deck of the boat before diving to get on the boat going to the left there is a wide opening due to the boat that breaks up
In this opening we see the corridors leading to the sleeping cabins and down the hall stands a terrorist.
Unable to shoot from the bridge to believe once again that there is bulletproof glass while it is perfectly exposed, he can not even see me because he does not attack me so to have it go down
frustrating that developers have not seen it
Other than that the plates are very well stashed
.