Blunt-winged Warbler 
(Chích cánh cụt, Acrocephalus concinens)

The blunt-winged warbler (Acrocephalus concinens) is a marsh-warbler (family Acrocephalidae).

The bird is found in Afghanistan, Pakistan, Northeast India and China; winters in Myanmar, Thailand and Bangladesh.

The family is from the name of the genus Acrocephalus from Ancient Greek akros, "highest", and kephale, "head". 
It is possible that the Naumanns thought akros meant "sharp-pointed".
concinens Latin concinens singing (concinere to sing in chorus, to harmonise).