How old is the bitch and when was she last in season. Is she due to come in season?
When your bitch comes into season or is coming in you need to separate the males or keep her entirely away from them so that your young entire male doesn't need to fight for her.
Your young entire male will now take over as boss and you have to allow that to happen.
When you keep entire dogs together more than just a couple you can expect the odd scuffle. Your breed is strong minded and active.
During this time keep the exercise up to the males, brain training and obedience.
Hurry up and get them out to some shows so that you are certain you are going thru all this for a reason.
Maintain yourself as leader thru calm assertive leadership. Speak to some breeders of your breed to get more knowledge. Owning entire dogs is a different kettle of fish to owning de-sexed dogs.