Perhaps you should try some spelling variations:
thien van » thi van
hanh vai » hanh vi, hanh va, hanh tai
cac thuc » cach thuc, cac thu, can thuc
hieu van » hieu va, lieu va, hieu ve
su sach » vu sach
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
cao hoi » cau hoi, co hoi, cao hoc
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet
v nang » va nang, vu nang, van nang

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) or (so sach)) v nang cao hoi. ((hieu van) or (thien van)) cac thuc va hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) v nang cao hoi. ((hieu van) OR (thien van)) cac thuc va hanh vai cua tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sach)) v nang cao hoi. ((hieu van) or (thien van)) cac thuc va hanh vai cua tre*.