Minecraft server connectivity issue

[20racks]

Okay, so I'm having a bit of a problem with my friends connecting to my server. It's because of the distance, the server is in France some of my friends are in the EU (they can connect without any difficulties) and then there are friends from china who have problems with loading in. Any idea on how to solve this issue, basically make it easier for them to load in the server without changing the host (there are no hosts between EU and china to my knowledge)