This bug always happens at military bases inside the barracks buildings.
To my knowledge this only happens with jackets or pants.
Whenever I find pants or jackets under the beds, I first go into 1st person.
I attempt to see if I can grab the item by crouching and staring directly at the item in question, it doesn't work. I keep staring directly and press tab, they still won't show up. What I end up doing is going prone in attempt to see if that helps to get closer, it still doesn't work.
EDIT: WHEN YOU LOOK AT THEM, THE NAME DOESN'T EVEN APPEAR THEREFORE YOU CANNOT USE MOUSE BUTTON 3.