Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh di » thanh doi, thanh de, thanh do
te sach » toc sach
hieu va » lieu va, hieu qua
luc ban » duc ban, cuc ban, luc bat
cao luc » bao luc, cao duc, cao suc
vu nang » vuc nang, va nang, vu dang
cua tre » cua te, cuu tre, cua triet
va cao » va cac, va co, va dao
v nang » va nang, van nang, voi nang
di cua » dai cua, doi cua, de cua
x hoi » xa hoi, o hoi, 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: te sach ((v nang) or (vu nang)) ((x hoi) or (x ho)). hieu va cao luc ban thanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((v nang) OR (vu nang)) ((x hoi) OR (x ho)). hieu va cao luc ban thanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: te sach ((v nang) or (vu nang)) ((x hoi) or (x ho)). hieu va cao luc ban thanh di cua tre*.