Perhaps you should try some spelling variations:
vanh dai » van dai, vanh tai, lanh dao
te sach » toc sach
hieu va » lieu va, hieu qua
cac luc » cau luc, coc luc, cac nuoc
va vanh » va van, va danh, va hanh
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
luc va » duc va, tuc va, loc va
x 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: te sach y nang ((((x hoi) OR (x ho))) OR (xa hoi)). hieu va cac luc va vanh dai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang ((((x hoi) OR (x ho))) or (xa hoi)). hieu va cac luc va vanh dai cua tre~".
• Adding a wildcard symbol may retrieve word variants: te sach y nang ((((x hoi) OR (x ho))) or (xa hoi)). hieu va cac luc va vanh dai cua tre*.