Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hanh doanh » hang doanh, chinh doanh, doanh doanh
doanh luan » doanh nhan
luan nhung » luan chung, luan hung, quan nhung
nhung cong » dung cong, thong cong, hang cong
hieu sang » chieu sang, hieu lang, nhieu tang
cong dan » cong san, cong tan, huong dan
than cau » toan cau, phan cau, than cap
phan dau » phan tu, hang dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu sang) OR (hieu quang)) - hanh doanh luan nhung cong dan ((than cau) or (phan dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu sang) OR (hieu quang)) - hanh doanh luan nhung cong dan ((than cau) OR (phan dau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu sang) OR (hieu quang)) - hanh doanh luan nhung cong dan ((than cau) or (phan dau))".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu sang) OR (hieu quang)) - hanh doanh luan nhung cong dan ((than cau) or (phan dau))*.