Perhaps you should try some spelling variations:
hanh doanh » hang doanh, chinh doanh, doanh doanh
hieu lang » chieu sang, hieu quang, nhieu tang
doanh cua » doanh luan
tong cong » trong cong, cong cong, dang cong
dung cong » dung trong
hoc hieu » hoc thieu, hoc hien, doc hieu
huy van » thuy van, duy van, quy van

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu lang - hanh doanh cua ((tong cong) or (dung cong)) huy van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - hanh doanh cua ((tong cong) OR (dung cong)) huy van ban.
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - hanh doanh cua ((tong cong) or (dung cong)) huy van ban*.