Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
va danh » va dinh, va dan, dia danh
cua tre » cua te, cua triet, dua tren
va hanh » van hanh, va thanh, ban hanh
cuu tre » cau tren, cau treo
cac tuc » cac toc, cac tu, cac tac
qua cac » cua cac
nang xa » nang x, lang xa, nang ma
y nang » ky nang, ly nang, v nang

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 hoi. hieu qua cac tuc ((va danh) OR (va hanh)) di ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang xa hoi. hieu qua cac tuc ((va danh) OR (va hanh)) di ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y nang xa hoi. hieu qua cac tuc ((va danh) OR (va hanh)) di ((cua tre) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: toc sach y nang xa hoi. hieu qua cac tuc ((va danh) OR (va hanh)) di ((cua tre) or (cuu tre))*.