Males benefit from neutering by eliminating spraying and hormone-related aggression. Check with your veterinarian. If you notice your rabbit drooling this is usually an indication of misarranged teeth, which is common. The rabbit's teeth are always growing and need wearing down by chewing on twigs. The drooling means the teeth are not wearing down properly and need your veterinarian needs to do some trimming.
Hairballs are a common cause of death in rabbits.
They groom the same way cats do, by licking their coats. The difference is the rabbit does not vomit up the hair that was ingested. This is a major reason for hay in their diet, which creates the fiber to prevent this problem. You may also use cat hairball medicines such as Petromalt or Laxatone once a week and daily during their molt. Exercise is also important.