Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
hieu van » thien van, lieu va, hieu ve
su sach » vu sach
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
so sach » so sanh, bo sach, co sach
cac lo » cac lop, cac co, cac bo
x hoi » xa hoi, o hoi, x ho
lo va » lo van, lao va, ly va

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