Hello,
To correct your question sentence -
"One of the client which have version of 12.1. It comes from other location and is unmanaged client. Will i be able to manage it from my manager?"
Answer:
You would be able to manage SEP 12.1 client from SEPM 12.1
However, In your case since you have SEPM 11.0.7101 and SEP 12.1 client, you would have to Upgrade the SEPM to the Latest version of SEP 12.1 OR Uninstall SEP 12.1 from the machine and then install a SEP 11.x client on the same.
Hope that helps!!