Perhaps you should try some spelling variations:
trinh quan » tinh quang, trinh luat, trinh han
hieu manh » chieu xanh, hieu nganh, dieu hanh
hang cong » dang cong, bang cong, thanh cong
hang nong » thang long, han tong
hoc hieu » hoc thieu, hoc hien, doc hieu
sinh cua » manh cua, dinh cuu, sinh va
san toan » van toan, dan toan, manh toan
toan cau » toan cao, toan ban, toan tap

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 manh - hanh ((sinh cua) or (trinh quan)) ((hang cong) or (hang nong)) san toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - hanh ((sinh cua) OR (trinh quan)) ((hang cong) OR (hang nong)) san toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - hanh ((sinh cua) or (trinh quan)) ((hang cong) or (hang nong)) san toan cau*.