if one is a member of tzu chi foundation,
he will always use the phrase "感恩" instead of "謝謝" , "謝謝你" or "多謝".
the phrase "感恩" is getting popular in taiwanese' daily oral expression.
the vietnamese "cám ơn" which means "thank you"
is derived from chinese 感恩.
for more information about tzi chi foundation,
please visit their website
http://www.us.tzuchi.org/usa/home.nsf/home/index?OpenDocument (english-usa)
or
http://tw.tzuchi.org/index.php (chinese-taiwan)