丈二和尚,摸不着头脑

zhàng èr hé shang , mō bu zháo tóu nǎo

lit. like a three-meter high monk, you can't rub his head (idiom)

fig. at a total loss

zhàng

measure of length, ten Chinese feet (3.3 m)

èr

two

(literary) harmonious (variant of 和[he2])

shang

still

,

to feel with the hand

bu

no; not so

zháo

to touch

tóu

head

nǎo

brain