Perhaps you should try some spelling variations:
hong cuong » hong vuong, hung cuong, thong chuong
tong cuong » tang cuong, tong cong, thong chuong
hieu cach » hieu cac, chieu sach, hieu ca
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
hoc hieu » hoc thieu, hoc hien, doc hieu
doan cau » toan cau, doan dau, doan cap
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 cach - hanh tinh chat ((tong cuong) or (hong cuong)) tap ((doan cau) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu cach - hanh tinh chat ((tong cuong) OR (hong cuong)) tap ((doan cau) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: hoc hieu cach - hanh tinh chat ((tong cuong) or (hong cuong)) tap ((doan cau) or (toan cao))*.