Perhaps you should try some spelling variations:
bao thuc » cao thuoc, am thuc, va thuc
so sach » bo sach, co sach, hoc sach
hieu va » lieu va, hieu qua
so sanh » do sanh
hang di » hang doi, hang vi, hang dien
va hang » van hang, va nang, va lang
xang xa » lang xa, mang xa, ang xa
hieu ve » hieu van
thuc va » thuc vat, thuc dan, thuc day
di cua » dai cua, doi cua, de cua
cua tu » cua tuc, cua su, cua cu
y xang » ty xang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) OR (so sanh)) y xang xa hoi. ((hieu ve) or (hieu va)) bao thuc va hang di cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) y xang xa hoi. ((hieu ve) OR (hieu va)) bao thuc va hang di cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (so sanh)) y xang xa hoi. ((hieu ve) or (hieu va)) bao thuc va hang di cua tu".
• Adding a wildcard symbol may retrieve word variants: ((so sach) OR (so sanh)) y xang xa hoi. ((hieu ve) or (hieu va)) bao thuc va hang di cua tu*.