Blyth's Leaf warbler 
(Chích đuôi xám, Phylloscopus reguloides)

Blyth's leaf warbler (Phylloscopus reguloides) is a species of leaf warbler (family Phylloscopidae).
It is found mainly in Southeast Asia, southern China and along the Himalayas till northern Pakistan.

The name Phylloscopus combines the Ancient Greek phullon meaning "leaf" and skopos meaning "seeker" (from skopeo, "to watch").
reguloides: Greek -oides resembling.
Regulus: Latin: regulus prince, kinglet (dimimunitive rex, regis king), from genus Regulus: kinglet,
goldcrest.