Perhaps you should try some spelling variations:
sach thien » sach thieu, sach tien, cach thien
thien nang » thien bang, thien dang, trien nang
hieu van » hieu va, thien van, lieu va
lam thuc » lam thuoc, am thuc, nam thuc
va thanh » gia thanh, ban thanh, va tinh
thanh vi » hanh vi, thanh va, thanh ve
dua tren » dung tren
cau tren » cu tren, dau tren, ca tren
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
van lam » van nam
thuc va » thuc vat, thuc dan, thuc day

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 thien nang xa hoi. hieu van lam thuc va thanh vi ((dua tren) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thien nang xa hoi. hieu van lam thuc va thanh vi ((dua tren) OR (cau tren)).
• Adding a wildcard symbol may retrieve word variants: su sach thien nang xa hoi. hieu van lam thuc va thanh vi ((dua tren) or (cau tren))*.