Greenish Warbler 
(Chích xanh lục, Phylloscopus trochiloides)

The greenish warbler (Phylloscopus trochiloides) is a widespread leaf warbler with a breeding range in northeastern Europe, and temperate to subtropical continental Asia. 
This bird is strongly migratory and winters in India.
The specific trochiloides is from Ancient Greek trokhalos, "bowed", and -oides "resembling", from the similarity to the willow warbler, P. trochilus.

Leaf warblers are small insectivorous passerine birds belonging to the genus Phylloscopus. 
Leaf warblers were formerly included in the Old World warbler family but are now considered to belong to the family Phylloscopidae, introduced in 2006.
The name Phylloscopus combines the Ancient Greek phullon meaning "leaf" and skopos meaning "seeker" (from skopeo, "to watch").
The specific trochiloides is from Ancient Greek trokhalos, "bowed", and -oides "resembling", from the similarity to the willow warbler, P. trochilus.
The specific epithet trochilus is Ancient Greek meaning "wren".