Perhaps you should try some spelling variations:
doanh doanh » toan doanh, doanh hoan, doanh thanh
quang nhung » quang hung, quan nhung, quang phuong
dung phuong » dung thuong, bang phuong, dung chung
hieu quang » thieu quang, hieu quan, hieu qua
hieu lang » chieu sang, nhieu tang, hieu van
ban nhanh » ban hanh, ban thanh, ban nhan
nhanh cay » nhanh ha, nhanh bac, nhanh va
cong ban » cong bang, cong san, cong tan

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) OR (hieu quang)) - doanh doanh ((quang nhung) or (dung phuong)) cong ban nhanh cay~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu lang) OR (hieu quang)) - doanh doanh ((quang nhung) OR (dung phuong)) cong ban nhanh cay.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu lang) OR (hieu quang)) - doanh doanh ((quang nhung) or (dung phuong)) cong ban nhanh cay".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu lang) OR (hieu quang)) - doanh doanh ((quang nhung) or (dung phuong)) cong ban nhanh cay*.