You really don't.

If you want something similar find some inexpensive pair of short running shorts on Amazon like:

https://www.amazon.com/Baleaf-Quick-Dry-Lightweight-Running-Shorts/dp/B01FJPW94A/ref=mp_s_a_1_5?dchild=1&keywords=running+shorts+for+men&qid=1625398657&sprefix=runni&sr=8-5

The Muay Thai shorts are just unnecessarily expensive while those running shorts are more comfortable.