Your dogs need an outlet for their energy. They need more physical and mental excercise. The dogs are bored and coming up with something to do.
That being said you can set up a barrier and it works up to so many feet. You can bury the wire or leave it on the ground. Isnt always perfect though. Her aunt had a dog that figured out if it got a running start and jumped through the shock it would quit shocking once he cleared the barrier.
Here is a link for an option.
www.gundogsupply.com/dog-fence.html