Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
te sach » toc sach
duc ban » duc tan, duc van, dua ban
hai cua » thai cua, dai cua, hoi cua
bai cua » ban cua, dai cua, bai ca
van cao » van dao, van bao, van hao
cao duc » dao duc, cao suc, giao duc
y nang » ky nang, ly nang, v nang
o hoi » co hoi, o hoc, o hai
x hoi » xa 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: te sach y nang ((x hoi) OR (o hoi)). hieu van cao duc ban thanh ((bai cua) or (hai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang ((x hoi) OR (o hoi)). hieu van cao duc ban thanh ((bai cua) OR (hai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang ((x hoi) OR (o hoi)). hieu van cao duc ban thanh ((bai cua) or (hai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: te sach y nang ((x hoi) OR (o hoi)). hieu van cao duc ban thanh ((bai cua) or (hai cua)) tre*.