Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
qua cham » qua cac, va cham, qua cua
cau treo » cau theo, cau tren, cau triet
nang xa » nang x, lang xa, nang ma
qua hai » qua hoat
va danh » va dinh, va dan, va hanh
danh di » danh du, xanh di, danh dien
cua tre » cua te, cuu tre, cua triet
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 cham) OR (qua hai)) duc va danh di ((cua tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang xa hoi. hieu ((qua cham) OR (qua hai)) duc va danh di ((cua tre) OR (cau treo)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y nang xa hoi. hieu ((qua cham) OR (qua hai)) duc va danh di ((cua tre) or (cau treo))".
• Adding a wildcard symbol may retrieve word variants: toc sach y nang xa hoi. hieu ((qua cham) OR (qua hai)) duc va danh di ((cua tre) or (cau treo))*.