problem with colliders

Unity Engine
1

Sometimes, one collider just go through another. Why this could happens?One collider is thin plane, and other is fast moving sphere. P.S. Sorry for my english.

2

If its Unity5, try using “Continuous collision detection”
More info about it:

Its its Unity4.x, see here for resources/scripts: Fast Projectiles « Unity Coding – Unity3D (see comments also)

3

thanks a lot!