1) Are they neutered? Neutering may help 'calm them down'
But 2) they are bunnies, digging and foraging and getting in to small spaces is what they do, so its better to provide them with their own safe secure run with supervised free-range time. Also provide digging boxes (which can be just a litter tray filled with soil) and tunnels and toys in their run. You can make your own cheaply, toys dont have to cost a lot of money.
Also you could try growing your own bunny-safe herbs so that they have more variety and stimulation.
You can fence off with that bending green garden wire stuff any unsafe bushes or areas that you dont want them to get to.