If your clients need to access the local network of your router, then you must push its routes to openvpn clients. For example, if your router has a 192.168.1.0/24 on it, then
push "route 192.168.1.0 255.255.255.0"
on the server config would allow your clients to access the network.
Alternatively, you can have
route 192.168.1.0 255.255.255.0
on client config. But that would be client specific you know.
