Perhaps you should try some spelling variations:
doanh doanh » toan doanh, doanh hoan, doanh thanh
hieu quang » thieu quang, hieu quan, hieu qua
khong cong » thong cong, khong cang, chong cong
hieu lang » chieu sang, nhieu tang, hieu van
doanh cua » doanh luan
cua khong » hua khong, cua phuong, cua thuong
cong san » cong tac
nvan tai » nhan tai, nan tai, nganh tai
van tai » von tai, van tuan

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((hieu lang) OR (hieu quang)) - doanh doanh cua khong cong san ((van tai) or (nvan tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu lang) OR (hieu quang)) - doanh doanh cua khong cong san ((van tai) OR (nvan tai)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((hieu lang) OR (hieu quang)) - doanh doanh cua khong cong san ((van tai) or (nvan tai))".
• Adding a wildcard symbol may retrieve word variants: theo ((hieu lang) OR (hieu quang)) - doanh doanh cua khong cong san ((van tai) or (nvan tai))*.