Perhaps you should try some spelling variations:
vanh dai » van dai, vanh tai, lanh dao
te sach » toc sach
sach ty » sach y, sach tu, sach thu
hieu va » hieu qua
cac luc » cau luc, cac nuoc, cac cuoc
va vanh » va van, va danh, va hanh
cua tre » cua te, cuu tre, cua triet
xang x » nang x
x hoi » xa hoi, o hoi, x ho

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 ty xang x hoi. ((hieu va) OR (lieu va)) ((cac luc) or (coc luc)) va vanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty xang x hoi. ((hieu va) OR (lieu va)) ((cac luc) OR (coc luc)) va vanh dai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty xang x hoi. ((hieu va) OR (lieu va)) ((cac luc) or (coc luc)) va vanh dai cua tre*".