The more thick glass stops more?

Not necessarily, the composition of the glass plays a crucial role in the ability to stop bullets. Especially if you consider not out shrapnel into the interior of the vehicle. This is very important because hit a glass not only seeks to stop the bullets that also protect the integrity of the occupants inside the vehicle.

You can stop a bullet, but splinters of glass that are generated by the impact can cause serious damage to a person who is within the interior of the vehicle.
The composition and the manufacturing process of the glass than the thickness as such is more important. Therefore the thickness does not determine the level of protection or a glass ballistic level.