Camera goes through landscape hills.

Hello everybody.
My cam goes through the hills of the landscape in a very weird way.

Collision Mip Level and Simple Collision Mip Level=0

Cam jumps into the landscape and cant be zoomed.

Collision Mip Level and Simple Collision Mip Level=5

Everything seems to be OK, but if we zoom in…

…another bug happens.

I don’t like both variants. Is there any way for cam mesh to move just above the ground level in order to prevent going through the landscape like it happens usind the 2nd variant? Or maybe someone can offer more reasonable way of fixing it.
Thanks in advance.