Perhaps you should try some spelling variations:
mai khoi » mai khoa, cac khoi, dai khoa
tai khoa » da khoa, noi khoa
hieu van » hieu va, thien van, hieu ve
hanh vai » hanh vi, hanh va, hanh tai
ky tang » ky nang, ky dang, kho tang
dao duc » giao duc, tao duoc
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet

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 khoi) or (tai khoa)). ((hieu van) or (lieu va)) dao duc va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky tang ((mai khoi) OR (tai khoa)). ((hieu van) OR (lieu va)) dao duc va hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu cac ky tang ((mai khoi) or (tai khoa)). ((hieu van) or (lieu va)) dao duc va hanh vai cua tre*.