MS Remote Desktop Issuessss
The answer is going to be more complex than you want, and someone else is going to recommend a service or web application that hides the complexity from you. The reason you are unable to reach your work computers from another network is because when on your internal network you have network access to the internal network. As long as you can reach the Internet from inside the internal network, you have a gateway to other networks. When outside your internal network, you'd need to know the external address of that gateway, and that gateway would need to be configured to port forward any ports your remote desktop client needs to serve your work desktop remotely to you. Your question is really simplistic and any answer that provides you a solution is going to need more information from you, such as do you have an IT department? Have you asked for remote access to your work terminal? That's kind of their job, so I'd make them do it.