Email issue

Email issue

I set in CRM a department shared email form which I want my men write to their contact. It is fine but if a contact reply to the same email, the answer will not appear in Zoho. I can only see sent email but not the "inbox" ones...
Can you help me?
I want having 4 account, each for my guys. Each guys must receive, on shared email, only messages from contacts whom he is the owner and answer to them. Is it possible?
Thanks