Indian nuthatch 
(Trèo cây bụng hung, Sitta castanea)

The Indian nuthatch (Sitta castanea) is a species of bird in the family Sittidae. It is found in Bangladesh, India and Nepal.
This species has been split by Rasmussen and Anderton (2005) from the chestnut-bellied nuthatch.

The nuthatches are all in the genus Sitta, a name derived from sitte, Ancient Greek for this bird.
The English term nuthatch refers to the propensity of some species to wedge a large insect or seed in a crack and hack at it with their strong bills.
castanea: From Ancient Greek kastáneia, from kástana meaning chestnut or chestnut tree.