Perhaps you should try some spelling variations:
doanh dan » doanh ban, doanh van, doanh dao
sach thu » sach thue, sach tham, cach thuc
hieu van » hieu va, thien van, lieu va
nam truc » nam truoc, nam thuc, nam trung
va doanh » van doanh, vay doanh, va danh
nang xa » nang x, lang xa, nang ma
truc va » thuc va, thuc vat, trung va
ca tre » ca tren, cua tre, ca tru

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach thu) or (sach thieu)) nang xa hoi. hieu van nam truc va doanh dan ca tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach thu) OR (sach thieu)) nang xa hoi. hieu van nam truc va doanh dan ca tre.
• Adding a wildcard symbol may retrieve word variants: thu ((sach thu) or (sach thieu)) nang xa hoi. hieu van nam truc va doanh dan ca tre*.