After having a bit of a look around, I think it's probably one of the Asian Keelbacks, probably the Rednecked Keelback (Rhabdophis subminiatus) which includes Thailand in it's distribution. While the colouring seems to vary somewhat, it is characterised by the red neck, and often has the black teardrop.
My first idea of a Beauty Snake I've abandoned as they all have a stripe behind the eye.
the snake whos head is in the photo is a keelback, Rhabdophis subminiatus as Hix said, but the tail in the photo is probably from a Ptyas korros, a species of ratsnake.
Ptyas korros are the most evil tempered demons to ever wear scales, they get to about 8 feet long and can strike almost their whole length it would seem.
If it appears that I have been on the receiving end of more than one of these you would be correct.
Nice snakes though
by the looks of that slateman it some kind of culubrid . but see that soft seaweed or freshwater weed its on i think it could be a mildly poisonous swamp or tropical sea species kept in part fresh / part salt aquarium as above . in those countries they can transfer them to nurseries as these tropical colubrids are more native to those countries Thailand and Pukhet .
They may even find the species around local where the nursery is in Thailand and Pukhet .
Well slateman thats what i think but some peple might think me an expert . i do keep my heads in the books lol.
I mightnt know anything at all!!