$ sudo apt-get update
$ sudo apt-get install fonts-khmeros-udeb 

fonts-khmeros-udeb is installed in your system.

Make ensure the fonts-khmeros-udeb package were installed using the commands given below,

$ sudo dpkg-query -l | grep fonts-khmeros-udeb *

You will get with fonts-khmeros-udeb package name, version, architecture and description in a table

fonts-khmeros-udeb package basic information: