Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
may thoi » gay thoi, may thi, tay thoi
ky mang » ky nang, ke mang, ky dang
hieu va » lieu va, hieu qua
cam tuc » cam xuc, cam tu, nam thuc
va hanh » van hanh, va thanh, va danh
su cac » tu cac, su cao, su can
va cam » va cham, va cac, va cao
vi hoa » voi hoa, vi hoc, va hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su cac ky mang may thoi. hieu va cam tuc ((va hanh) or (ban thanh)) vi hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su cac ky mang may thoi. hieu va cam tuc ((va hanh) OR (ban thanh)) vi hoa viet.
• Adding a wildcard symbol may retrieve word variants: su cac ky mang may thoi. hieu va cam tuc ((va hanh) or (ban thanh)) vi hoa viet*.