Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
van hanh » van thanh, ban hanh, van anh
sach thu » sach thue, sach thieu, sach tham
dao tuc » dao duc
tuc van » thuc van, truc van, tuc va
hieu va » hieu qua
sach tu » cach tu, sach ty, sach uu
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((sach tu) or (sach thu)) nang xa hoi. ((hieu va) or (lieu va)) dao tuc van hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach tu) OR (sach thu)) nang xa hoi. ((hieu va) OR (lieu va)) dao tuc van hanh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: toc ((sach tu) or (sach thu)) nang xa hoi. ((hieu va) or (lieu va)) dao tuc van hanh dai cua tre*.