Perhaps you should try some spelling variations:
thanh ca » thanh cha, thanh cac, thanh ha
va thanh » gia thanh, ban thanh, va tinh
lang van » dang van, tang van, hoang van
su sach » so sach, vu sach
cao duc » dao duc, cao suc, giao duc
sach ty » sach y, sach tu, sach thu
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay
cua tre » cua te, cuu tre, cua triet
ca cua » co cua

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 ty ((lang xa) OR (lang van)) hoi. ((hieu ve) or (hieu qua)) cao duc va thanh ca cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((lang xa) OR (lang van)) hoi. ((hieu ve) OR (hieu qua)) cao duc va thanh ca cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((lang xa) OR (lang van)) hoi. ((hieu ve) or (hieu qua)) cao duc va thanh ca cua tre*".