Perhaps you should try some spelling variations:
sach thue » sach thu, sach thieu, cach thuc
sach tham » sach nha
cau tren » cu tren, dau tren, ca tren
nang xa » nang x, lang xa, nang ma
va dinh » van dinh, va kinh, va tinh
dinh vi » dinh ve, dinh viet, dinh tri
dam tu » nam tu, cam tu, dam thuc
tam tu » nam tu, cam tu, tam thuc
vi cau » va cau, ve cau, di cau

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 thue) OR (sach tham)) nang xa hoi. hieu qua ((dam tu) or (tam tu)) va dinh vi cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach thue) OR (sach tham)) nang xa hoi. hieu qua ((dam tu) OR (tam tu)) va dinh vi cau tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach thue) OR (sach tham)) nang xa hoi. hieu qua ((dam tu) or (tam tu)) va dinh vi cau tren*".