Ok, so you want to manage your ASA from a network connected via site to site VPN tunnel. No prob. Two easy steps makes this happens.
First you have to add the network as an allowed access via the inside network. (I will use the 192.168.1.0/24 network in my example)
From CLI it’s:
http 192.168.1.0 255.255.255.0 inside
If this was a directly connected network then that is all you would have to do, however since it is connected from VPN you also need to specify the inside interface as a management interface with this command.
You can do all this from the ASDM as well:
Under Configuration, Device Management, Management Access:
Add the network on the inside interface in the ASDM/HTTPS/Telnet/SSH section
Then enable management access on the inside network under the Management Interface section