Perhaps you should try some spelling variations:
mai khoi » mai khoa, tai khoa, cac khoi
van hanh » van thanh, ban hanh, van anh
hanh vai » hanh vi, hanh va, hanh tai
ky tang » ky nang, ky dang, kho tang
mai hoi » dai hoi, lai hoi, mai doi
van cao » van bao, van hao, van cau
duc van » duc va, duc tan, duc manh
vai cuu » vai cua
cuu tre » cua tre, cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ky tang ((mai hoi) OR (mai khoi)). hieu ((van cao) or (van dao)) duc van hanh vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky tang ((mai hoi) OR (mai khoi)). hieu ((van cao) OR (van dao)) duc van hanh vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky tang ((mai hoi) OR (mai khoi)). hieu ((van cao) or (van dao)) duc van hanh vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu cac ky tang ((mai hoi) OR (mai khoi)). hieu ((van cao) or (van dao)) duc van hanh vai cuu tre*.