covered in/covered with

Please tell me, what is the diffference between: covered in and covered with, and when should I use either of them?
Many thanks!!!

Could you give us the examples in which you bumped into them? Mostly, the Earth is covered with water.

Here you are, from the TOEIC listening exercises:
covered in white clouds (about sky)
covered in large rocks (about hillside)
covered with pictures (woman’ s desk)
covered with snow (mountain tops)

can’t it be: covered with large rocks?? covered with white clouds?

Hi Saneta,

‘Covered in’ suggests simply a description of how something looks and doesn’t mean the whole area. ‘Covered with’ suggests that the whole surface is covered with pictures/snow or whatever.