How do I train my dogs on paper

Dog eats paper

We took over an emergency dog ​​from a private person three months ago. He is almost three years old and the big lot for us and the dog, who has been part of our family for over four years. He's got one little problem though, and we're not quite sure how to stop him: Rocky eats paper. He only eats it when he is unobserved, and he also knows not to eat it. We were aware of this problem when we took over the dog, but we thought it might have to do with boredom and would go away quickly with us. There is no such thing as boredom in our large family.
Unfortunately, it is the case that you can no longer go to the toilet without the lout tearing up some important documents. He's obviously used to a box, so that's not a problem if the dogs have to be alone for an hour or two. Only those little moments are difficult when you go to the mailbox or the garbage can and the dog thinks he is not being watched.
Rocky is a Border Collie-Labrador mix. He was very overweight, but has already lost twelve pounds and has to lose about eight pounds before he is healthy and fit. So far he has lived together in a small apartment with a very dominant Labrador mongrel (male). His owners didn't have much time for him, but he was very well brought up. And unfortunately fed a little too much. Otherwise everything is really perfect.

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