Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
diem cau » dieu can
te sach » toc sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
va dam » van dam, va dao, va dau
dam tu » nam tu, cam tu, tam tu
di cau » da cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach thu nang xa hoi. hieu va dam tu va hanh ((di cau) or (diem cau)) tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach thu nang xa hoi. hieu va dam tu va hanh ((di cau) OR (diem cau)) tren.
• Adding a wildcard symbol may retrieve word variants: te sach thu nang xa hoi. hieu va dam tu va hanh ((di cau) or (diem cau)) tren*.