This thread is resolved. Here is a description of the problem and solution.
Problem:Khmer (Cambodian) Language
Solution:With WPML plugin you get the 60 pre-configured languages added by us which you can add by going to WPML->Languages->Add/Remove languages
We also do give you the ability to add any custom language by going to WPML->Languages->Edit languages->Add new language
you can find the default locale for the language Khmer here -> https://make.wordpress.org/polyglots/teams/
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