Cognomen ธรรมชนก (ธรรมชนก , Thamchanok , Thumchanok) , worldwide, is an extremely rare surname. Much more prevalently, ธรรมชนก is the forename as well as the last name.
Thammachanok
ธงชัยบริสุทธิ์, and ประจิตต์
, Thamchanok