Perhaps you should try some spelling variations:
van thanh » van tuan
ban thanh » ban hanh, ban hang
sach thu » sach thue, sach thieu, sach tham
cuu tre » cua tre, cau tren, cau treo
dau tuc » dau tu, dao tuc, cau truc
sach ty » sach y, sach tu, xach tay
nang xa » nang x, lang xa, nang ma
di cuu » di cau, di cua, dinh cuu
va dau » va dao

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 ty) OR (sach thu)) nang xa hoi. lieu va dau tuc ((van thanh) or (ban thanh)) di cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach thu)) nang xa hoi. lieu va dau tuc ((van thanh) OR (ban thanh)) di cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach thu)) nang xa hoi. lieu va dau tuc ((van thanh) or (ban thanh)) di cuu tre*".