Perhaps you should try some spelling variations:
hien xanh » hien hanh, hien nhanh, chieu xanh
tranh qua » thanh qua, trinh qua, tranh quang
tranh cua » doanh cua, manh cua
dung cong » dung trong
cong dan » cong san, cong tan, huong dan
than cap » khan cap, thanh lap, thanh cac
hang dau » hang va, hang tai

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - canh ((tranh qua) OR (tranh cua)) dung cong dan ((than cap) OR (hang dau))~.
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - canh ((tranh qua) or (tranh cua)) dung cong dan ((than cap) or (hang dau))*.