Ok, here are scenarios:
Webserver: 192.168.0.10:80
1. Windows 10, Desktop PC - 192.168.0.3 = no connection
2. Window 10, Laptop - 192.168.0.4 = no connection
3. Window 10, Desktop PC at work - 10.8.0.2 OpenVPN = ok
4. Android (mobile phone), outside home - 10.8.0.3 OpenVPN = ok
5. Android (same...