Perhaps you should try some spelling variations:
dan thanh » dang thanh, danh thanh, ban thanh
sach tham » sach nha
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
thanh de » hanh de, thanh ve, thanh do
thuc dan » thuc hanh, hoc dan, thuc vat
sach thu » sach thue, sach thieu, cach thuc
nang xa » nang x, lang xa, nang ma
cua tu » cua tuc, cua su, cua cu

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 thu) OR (sach tham)) nang xa hoi. hieu van nam thuc dan thanh de ((cua te) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach thu) OR (sach tham)) nang xa hoi. hieu van nam thuc dan thanh de ((cua te) OR (cua tu))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach thu) OR (sach tham)) nang xa hoi. hieu van nam thuc dan thanh de ((cua te) or (cua tu))*".