Looking at, say, adopting Chinese principle (5)
I believe the answer is:
eying
'looking at' is the definition.
(I've seen this before)
'say adopting chinese principle' is the wordplay.
'say' becomes 'eg'.
'adopting' means one lot of letters goes inside another.
'chinese principle' becomes 'yin' (I've seen this in another clue).
'eg' placed around 'yin' is 'EYING'.
(Other definitions for eying that I've seen before include "Looking at with interest" , "Fixated on" , "Watching closely" , "Observing" , "Interested in visual appearance" .)