Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
hieu van » thien van, hieu ve
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
hieu va » hieu qua
sang ma » tang ma, nang ma, sang tao
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. ((hieu van) or (((hieu va) or (lieu 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. ((hieu van) OR (((hieu va) OR (lieu va)))) cam xuc va hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky sang ma hoi. ((hieu van) or (((hieu va) or (lieu va)))) cam xuc va hanh vai cua tre*.