Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
van cam » van nam, van lam, van cau
cam duc » cam xuc, cao duc, pham duc
duc ban » duc tan, duc van, dua ban
ban anh » ban hanh, ban banh, ban danh
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » xa hoi, ma hoa, me hoi
anh vi » hanh vi, anh va, anh ve
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y nang ((ma hoi) or (mai hoi)). hieu van cam duc ban anh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((ma hoi) OR (mai hoi)). hieu van cam duc ban anh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((ma hoi) or (mai hoi)). hieu van cam duc ban anh vi cua tre*.