Perhaps you should try some spelling variations:
vanh dai » van dai, vanh tai, lanh dao
sach tu » sach thu, cach tu, sach ty
va pham » van pham, va phap, va phan
va vanh » va van, va danh, va hanh
nang o » nang co, nang ho, nang ro
duy va » duy vat, duy van, day va
cua te » cua tu
o hoi » co hoi, o hoc, o hai

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: tu ((sach y) OR (sach tu)) nang o hoi. lieu ((va pham) OR (va phat)) duy va vanh dai cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach y) or (sach tu)) nang o hoi. lieu ((va pham) OR (va phat)) duy va vanh dai cua te~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sach tu)) nang o hoi. lieu ((va pham) OR (va phat)) duy va vanh dai cua te*.