Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
dang xay » dang van, van xay
su sach » so sach, vu sach
vai cua » dai cua, hai cua, lai cua
dan vai » dan va, dan tai, dan vat
cao duc » dao duc, cao suc, giao duc
cac dac » cac dan, cac dai, cac bac
hieu va » lieu va, hieu qua
lang xa » lang ha, lang van
cua tre » cua te, cuu tre, cua triet
va dan » ca dan, va dao, va dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach thu ((lang xa) OR (dang xay)) hoi. hieu va ((cac dac) or (cao duc)) va dan vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thu ((lang xa) OR (dang xay)) hoi. hieu va ((cac dac) OR (cao duc)) va dan vai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thu ((lang xa) OR (dang xay)) hoi. hieu va ((cac dac) or (cao duc)) va dan vai cua tre*".