You have many special fonts such as Japanese, Korean or Chinese, but the fonts do not support Thai language. But if you want to support it I can translate it. I like to play this game But my friends are not good at English, there is only this way.
Consider contacting their support instead https://support.facepunchstudios.com/hc/en-us
I already contacted that website. He also told me to give suggestions on this website, haha.