Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
may thoi » gay thoi, may thi, tay thoi
va hanh » van hanh, va danh, ban hanh
ke mang » ke nang, ke trang
hieu va » lieu va, hieu qua
ky mang » ky nang, ky dang, ky tang
cam tuc » cam xuc, cam tu, nam thuc
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) OR (ke mang)) may thoi. hieu va cam tuc ((va hanh) or (va thanh)) vi hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su cac ((ky mang) OR (ke mang)) may thoi. hieu va cam tuc ((va hanh) OR (va thanh)) vi hoa viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su cac ((ky mang) OR (ke mang)) may thoi. hieu va cam tuc ((va hanh) or (va thanh)) vi hoa viet".
• Adding a wildcard symbol may retrieve word variants: su cac ((ky mang) OR (ke mang)) may thoi. hieu va cam tuc ((va hanh) or (va thanh)) vi hoa viet*.