wèn dào yú máng
lit. to ask a blind man the way (idiom)
fig. to seek advice from an incompetent
问
wèn
to ask; to inquire
道
dào
road; path (CL:條|条[tiao2],股[gu3])
于
yú
(of time or place) in; at; on
盲
máng
blind
