For now, try to keep them separate...until someone who knows more about this can come and give advice, could you post more about your dogs? Ages, breeds (or best guess if they're mixes), histories (if you know them) and their daily schedule (how much food, what kind, when they're exercised, when and how they're trained) are a good start...the more detail the better. Have they been for a thorough vet check recently? Not just a once-over, but bloodwork, etc...there may be an underlying medical issue.
I will warn you that from what I've heard from reliable sources, once female dogs decide they don't like each other, they typically don't stop....
Edit: And you'll probably get more help if you post in the training advice