Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
su sach » so sach, vu sach
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
hieu ve » hieu van
lai hoi » dai hoi, lai hoa, lai roi
ky sang » ky nang, ky dang, ky tang
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc va
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky sang ((ma hoi) or (lai hoi)). ((hieu ve) or (hieu va)) cam xuc va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky sang ((ma hoi) OR (lai hoi)). ((hieu ve) OR (hieu va)) cam xuc va hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky sang ((ma hoi) or (lai hoi)). ((hieu ve) or (hieu va)) cam xuc va hanh vai cua tre*.