Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
van hang » van khang, van hoang, van thang
thuc van » thuc vat, thuc dan, thuc va
nam thuc » nam thuoc, am thuc, nam thu
so sach » so sanh, bo sach, co sach
hang di » hang doi, hang vi, hang dien
hieu he » hieu ve, hiem he, hieu le
mai hoi » mai khoi, dai hoi, lai hoi
su viet » so viet
he nam » ha nam, nghe nam
ma hoi » xa hoi, ma hoa, me hoi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: so sach thu nang ((ma hoi) OR (mai hoi)). hieu he nam thuc van hang di ((va thiet) OR (su viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach thu nang ((ma hoi) OR (mai hoi)). hieu he nam thuc van hang di ((va thiet) or (su viet))~".
• Adding a wildcard symbol may retrieve word variants: so sach thu nang ((ma hoi) OR (mai hoi)). hieu he nam thuc van hang di ((va thiet) or (su viet))*.