Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hanh manh » hanh mang, lanh manh, hoang manh
dong cong » duong cong, dung cong, cong cong
dang cong » dung cong
hoi hieu » hoi phieu, hoi tieu, moi hieu
manh cua » doanh cua, ban cua
quy toan » huy toan, quyet toan, quoc toan
quy tuan » duy tuan, quy chuan, quy thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoi hieu quang - hanh manh cua ((dong cong) or (dang cong)) ((quy toan) OR (quy tuan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi hieu quang - hanh manh cua ((dong cong) OR (dang cong)) ((quy toan) OR (quy tuan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoi hieu quang - hanh manh cua ((dong cong) or (dang cong)) ((quy toan) OR (quy tuan)) cao".
• Adding a wildcard symbol may retrieve word variants: hoi hieu quang - hanh manh cua ((dong cong) or (dang cong)) ((quy toan) OR (quy tuan)) cao*.