How to connect to Oracle database on VM1 from host with 11gClient
It depends on the VM software you are using. In case of VirtualBox you have to check what type of connection you set (NAT, bridge, etc); if using NAT you need to enable a port-forward to the listener port: e.g. TCP 21521 on host, TCP 1521 on VM).

Also check if iptables firewall is enabled on your VM.