Perhaps you should try some spelling variations:
tinh dau » tinh da, trinh dan, trinh dao
te sach » toc sach
hieu ve » hieu va, hieu van
cac duc » cac du, cac dac, cac nuoc
cao duc » dao duc, cao suc, giao duc
va tinh » may tinh
dau cua » dai cua, day cua, cau cua
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.

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((y sang) OR (_ sang)) xa hoi. hieu ve ((cac duc) OR (cao duc)) va tinh 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 ve ((cac duc) or (cao duc)) va tinh dau cua tre~".
• Adding a wildcard symbol may retrieve word variants: te sach ((y sang) OR (_ sang)) xa hoi. hieu ve ((cac duc) or (cao duc)) va tinh dau cua tre*.