Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
qua pham » quan pham, quy pham, qua cham
cau treo » cau theo, cau tren, cau triet
ly nang » ky nang, ly hang, ly quang
ly vang » ly hang, ly van, ly quang
va danh » va dinh, va dan, va hanh
danh di » danh du, xanh di, danh dien
cua tre » cua te, cuu tre, cua triet

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 ((ly nang) or (ly vang)) xa hoi. hieu qua pham duc va danh di ((cua tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ly nang) OR (ly vang)) xa hoi. hieu qua pham duc va danh di ((cua tre) OR (cau treo)).
• Adding a wildcard symbol may retrieve word variants: toc sach ((ly nang) or (ly vang)) xa hoi. hieu qua pham duc va danh di ((cua tre) or (cau treo))*.