It is better to use private database links.
It is better for database links to point to a dedicated schema (not a table owner), then you can selectively grant to that user from multiple table-owner schemas, and create synonyms for the necessary objects.
But to be honest i dont get it ....
I dont know how this solve my problem because i already have public link on target db, and i need to include another user so that i can conect from one database to other with connection on two users....
Is it posible to create one dblink to another db, and then use it to connect on 2 diffrent remote users?
TBH I don't know the answer off the top of my head, and I haven't got time at the moment to look into this for you, but have you TRIED to create one link & then used it to connect with 2 different users? If so, did you get an error message telling you it couldn't be done? Or did it work? (in other words, if you try this yourself you may get a quicker response than waiting for someone else to do it for you)
90% of users' problems can be resolved by punching them - the other 10% by switching off their PCs.