Perhaps you should try some spelling variations:
nhung cuong » hung cuong, nhung chong, nhung huong
hanh tranh » hanh trinh, hanh trang, lanh tranh
nhung cong » dung cong, thong cong, hang cong
hieu manh » chieu xanh, hieu nganh, dieu hanh
hoc hieu » hoc thieu, hoc hien, doc hieu
tap toan » tap doan, tap quan, bai 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 tranh) OR (canh tranh)) cua ((nhung cuong) or (nhung cong)) tap toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - ((hanh tranh) OR (canh tranh)) cua ((nhung cuong) OR (nhung cong)) tap toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu manh - ((hanh tranh) OR (canh tranh)) cua ((nhung cuong) or (nhung cong)) tap toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - ((hanh tranh) OR (canh tranh)) cua ((nhung cuong) or (nhung cong)) tap toan cau*.