Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
cao duc » dao duc, cao suc, giao duc
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
y nang » ky nang, ly nang, v nang
va cao » va cac, va co, va dao
cua te » cua tu
cua cu » cua chu, cua cau, cua su
x hoi » xa hoi, o hoi, 5 hoi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((x hoi) OR (x ho)). hieu va cao duc va hanh va ((cua te) OR (cua cu))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang ((x hoi) OR (x ho)). hieu va cao duc va hanh va ((cua te) or (cua cu))~".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((x hoi) OR (x ho)). hieu va cao duc va hanh va ((cua te) or (cua cu))*.