The 2 dogs have been fighting with each other long enough now, it will be difficult or impossible for them to tolerate each other now. Possibly with a trainers help you may be able to reverse this. Since we are unable to see the dogs behavior that is the best advice.
Meanwhile, keep the 2 dogs separated - crate and rotate. They are crate trained right? If you have to have them out together, only do so if they are under complete control. They get toys, treats and fed separately and/or in the crate.
Again, get a trainer involved ASAP. You will learn to handle the dogs and avoid what is leading up to severe injuries or worse.