Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
cau treo » cau theo, cau tren, cau triet
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
qua nam » quan nam, cua nam, quang nam
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
nam tu » nam thu, nam thuc

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ky) or (sach thu)) nang xa hoi. hieu qua nam tu va hanh vi ((cua tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach thu)) nang xa hoi. hieu qua nam tu va hanh vi ((cua tre) OR (cau treo)).
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (sach thu)) nang xa hoi. hieu qua nam tu va hanh vi ((cua tre) or (cau treo))*.