Perhaps you should try some spelling variations:
chinh doanh » kinh doanh
canh doanh » hanh doanh, doanh doanh, kinh doanh
thong cong » trong cong, tong cong, thong thong
hieu lang » chieu sang, hieu quang, nhieu tang
cua thong » cua thuong, cua khong, cua tong
hoc hieu » hoc thieu, hoc hien, doc hieu
doan van » doan va, hoang van, luan van
dan van » dang van, dao van, tan 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 - ((canh doanh) or (chinh doanh)) cua thong cong ((dan van) OR (doan van)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu lang - ((canh doanh) OR (chinh doanh)) cua thong cong ((dan van) OR (doan van)) ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu lang - ((canh doanh) or (chinh doanh)) cua thong cong ((dan van) OR (doan van)) ban".
• Adding a wildcard symbol may retrieve word variants: hoc hieu lang - ((canh doanh) or (chinh doanh)) cua thong cong ((dan van) OR (doan van)) ban*.