Perhaps you should try some spelling variations:
nang dau » hang dau, xang dau, nang du
so sach » so sanh, co sach, hoc sach
bao luc » bao thuc
dau cua » dai cua, day cua, cau cua
bo sach » co sach, hoc sach
xang xa » lang xa, mang xa, ang xa
hieu ve » hieu van
va nang » van nang, da nang, cam nang
hieu va » lieu va, hieu qua
luc va » duc va, tuc va, loc va
cua su » qua su

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 (bo sach)) ty xang xa hoi. ((hieu ve) or (hieu va)) bao luc va nang dau cua su~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (bo sach)) ty xang xa hoi. ((hieu ve) OR (hieu va)) bao luc va nang dau cua su.
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (bo sach)) ty xang xa hoi. ((hieu ve) or (hieu va)) bao luc va nang dau cua su*.