Perhaps you should try some spelling variations:
chao chao » cao chat, cao cho, chat cho
cao chao » cao chat, cao cho, cao cap
sach su » cach su, sach tu, sach uu
te sach » toc sach
su dang » su dung
cua tre » cua te, cuu tre, cua triet
ha hoi » hoa hoi, xa hoi, va hoi
va dao » ca dao
dao vi » dao voi, dao ve, dao va
vi cua » vai cua, di cua
su va » su van, tu va

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 su dang ((ha hoi) OR (ha noi)). hieu ((cao chao) or (chao chao)) su va dao vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach su dang ((ha hoi) OR (ha noi)). hieu ((cao chao) OR (chao chao)) su va dao vi cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach su dang ((ha hoi) OR (ha noi)). hieu ((cao chao) or (chao chao)) su va dao vi cua tre*".