Perhaps you should try some spelling variations:
hien nhanh » hien hanh, thien thanh, dien thanh
tien thanh » tien thinh, tran thanh, den thanh
canh trinh » canh tranh, hanh trinh, canh tinh
thanh long » thanh cong, thang long, thanh huong
trinh ha » trinh han, trinh hoa, trinh nha
ha thanh » va thanh, pham thanh, phan thanh
long dan » long doan, cong dan, nong dan
khan cap » khan ap, khoan cam, phan cac
than cap » thanh lap, thanh cac, than cua

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 nhanh) OR (tien thanh)) - canh trinh ha thanh long dan ((khan cap) or (than cap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien nhanh) OR (tien thanh)) - canh trinh ha thanh long dan ((khan cap) OR (than cap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien nhanh) OR (tien thanh)) - canh trinh ha thanh long dan ((khan cap) or (than cap))".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien nhanh) OR (tien thanh)) - canh trinh ha thanh long dan ((khan cap) or (than cap))*.