Perhaps you should try some spelling variations:
hien manh » hien hanh, tien manh, hien nhanh
hieu manh » chieu xanh, hieu nganh, dieu hanh
thang cua » thong cua, hang cua, than cua
tong cong » trong cong, cong cong, dung cong
tang cua » mang cua, hang cua, tang luan
cong tam » cong tac, cong tan, cong nam
tam toan » tap toan, tam than, pham 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 ((hien manh) OR (hieu manh)) - hanh ((thang cua) or (tang cua)) tong cong tam toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien manh) OR (hieu manh)) - hanh ((thang cua) OR (tang cua)) tong cong tam toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien manh) OR (hieu manh)) - hanh ((thang cua) or (tang cua)) tong cong tam toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien manh) OR (hieu manh)) - hanh ((thang cua) or (tang cua)) tong cong tam toan cau*.