Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
vai cua » dai cua, hai cua, lai cua
cam tuc » cam xuc, cam tu, nam thuc
van cam » van nam, van lam, van cau
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
mai hoi » mai khoi, dai hoi, lai hoi
ky tang » ky nang, ky dang, kho tang
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, tuc xa
ma hoi » xa hoi, ma hoa, me hoi

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 ky tang ((ma hoi) or (mai hoi)). hieu van cam tuc va thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky tang ((ma hoi) OR (mai hoi)). hieu van cam tuc va thanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky tang ((ma hoi) or (mai hoi)). hieu van cam tuc va thanh vai cua tre*.