Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
cua triet » cua viet, su triet, va triet
thanh dai » thanh hai, thanh tai, thanh dat
cau tren » cu tren, dau tren, ca tren
lang van » dang van, tang van, hoang van
te sach » toc sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
tu ban » thu ban, te ban
va dao » ca dao

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 ky lang van hoa. hieu ((va bai) or (va dao)) tu ban thanh dai ((cua triet) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky lang van hoa. hieu ((va bai) OR (va dao)) tu ban thanh dai ((cua triet) OR (cau tren)).
• Adding a wildcard symbol may retrieve word variants: te sach ky lang van hoa. hieu ((va bai) or (va dao)) tu ban thanh dai ((cua triet) or (cau tren))*.