Perhaps you should try some spelling variations:
van khang » van khanh, van thanh, van quang
cua triet » cua viet, va triet
su triet » su viet, su tien, ve triet
nam thuc » nam thuoc, am thuc, nam thu
thu nang » thi nang, thu hang, thu bang
khang di » hang di, khang vi, khang voi
thuc van » thuc vat, thuc dan, thuc va
sach thu » sach thue, sach thieu, sach tham
so sach » so sanh, bo sach, co sach
hieu va » lieu va, hieu qua
ma hoi » mai hoi, xa hoi, me hoi
va nam » van nam, ha nam, va nay

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 (ma hoa)). hieu va nam thuc van khang di ((cua triet) OR (su triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach thu nang ((ma hoi) OR (ma hoa)). hieu va nam thuc van khang di ((cua triet) or (su triet))~".
• Adding a wildcard symbol may retrieve word variants: so sach thu nang ((ma hoi) OR (ma hoa)). hieu va nam thuc van khang di ((cua triet) or (su triet))*.