Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
danh dai » danh di, danh sai, vanh dai
danh dau » lanh dao, hang dau, danh tu
te sach » toc sach
van cao » van dao, van bao, van hao
cao duc » dao duc, cao suc, giao duc
cua tre » cua te, cuu tre, cua triet
y sang » duy sang
_ sang » _ san

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 sang) or (_ sang)) xa hoi. hieu van cao duc va ((danh dai) OR (danh dau)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((y sang) OR (_ sang)) xa hoi. hieu van cao duc va ((danh dai) OR (danh dau)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((y sang) or (_ sang)) xa hoi. hieu van cao duc va ((danh dai) OR (danh dau)) cua tre*".