Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thai tuc » thai thuc, thai thuy, thai hoc
dung sai » dung tai, dung va, dung dat
nang xa » lang xa, nang ma, mang xa
va thai » van thai, va tai, va tham
xa dung » xay dung, xa dong, va dung
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y ((nang xa) or (nang x)) hoi. lieu va thai tuc xa dung sai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y ((nang xa) OR (nang x)) hoi. lieu va thai tuc xa dung sai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y ((nang xa) or (nang x)) hoi. lieu va thai tuc xa dung sai ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: toc sach y ((nang xa) or (nang x)) hoi. lieu va thai tuc xa dung sai ((cua tre) OR (cuu tre))*.