Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
hanh vai » hanh vi, hanh va, hanh tai
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua
cua te » cua tu
x hoi » o hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky nang ((x hoi) or (xa hoi)). ((hieu van) or (hieu va)) pham duc va hanh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang ((x hoi) OR (xa hoi)). ((hieu van) OR (hieu va)) pham duc va hanh vai cua te.
• Adding a wildcard symbol may retrieve word variants: so sach ky nang ((x hoi) or (xa hoi)). ((hieu van) or (hieu va)) pham duc va hanh vai cua te*.