How do I fix grass disappearing when looking down?

Whenever I look down in first-person in my game on the grass, is disappears. I have read a few articles and when I change the x and y in the mouse-look script it does nothing. Is there a way to fix this?

The camera has a frustrum. It sees nothing that is too far away and nothing that is too close. Try making the near clipping plane closer to the actual point of the camera. This is done in the inspector for the camera. Eventually you will probably find that you need multiple cameras rendering objects at different distances. Tutorials are everywhere.