Perhaps you should try some spelling variations:
hieu lang » chieu sang, hieu quang, nhieu tang
quan ban » quang ban, qua ban, luan ban
quan van » luan van, quan va, quan luan
cong tac » cong ty
tac tren » rac tren, tai tren, tap tren
tren cay » trien cay, tren may, ten cay
ho hieu » ho chieu, hoi hieu, nho hieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho hieu lang - canh tranh ((quan ban) or (quan van)) cong tac tren cay~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - canh tranh ((quan ban) OR (quan van)) cong tac tren cay.
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - canh tranh ((quan ban) or (quan van)) cong tac tren cay*.