do you remember anything else from the MV?
what age would you say the singer was in?
did the singer seem to be full thai(asian) or mixed?
and the singer's hair was long? was it curly? layered? what was the color of the hair?
and what kind of music was it? was it hip hop, pop, or country? you have to becareful because the newer country songs in thailand, especially from female artists, tend to sound like pop music.
i hope i can help you. the list of singers that sutisa put up are very good singers. i hope you try to listen to their songs too.
OH, here is a good place for you to listen to good thai songs for free
www.ethaimusic.com they provide lyrics in thai and the translation of the song.