Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
cac tuc » cac toc, cac tu, cac tac
tuc van » thuc van, truc van, tuc va
van cau » van hau, van chat, toan cau
van dau » van dao, phan dau
ma hoi » xa hoi, ma hoa, me hoi
ve cac » va cac, vien cac

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky nang ((ma hoi) OR (mai hoi)). hieu ve cac tuc van hanh ((van cau) OR (van dau)) tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky nang ((ma hoi) or (mai hoi)). hieu ve cac tuc van hanh ((van cau) OR (van dau)) tren~".
• Adding a wildcard symbol may retrieve word variants: tu cac ky nang ((ma hoi) or (mai hoi)). hieu ve cac tuc van hanh ((van cau) OR (van dau)) tren*.