Oh and can you tell me how to say it phonetically

kwarm 'tayuh tayarn.' IMO a much more eloquent word than ambition. Just a hint though, if you're talking to folks that weren't born and raised with it, it'll mean very little to them, just like in most places in the world.

Oh and can you tell me how to say it phonetically

Depending on context a more common word would be “kayan” – although this really translates more accurately as “hard working”.

Patrick

ทะเยอทะยาน (tayer tayan) mean ambition. ขยัน (kayan) is only hardworking. Some people are "kayan"(working hard everyday). Just for life but not have ambition.

I agree with you all and another one word that can be used too is ความอยากได้อยากดี / kwarm yark dai yark dii /

I agree with you all and another one word that can be used too is ความอยากได้อยากดี / kwarm yark dai yark dii /

this could have a negative connotation - perhaps too ruthless!