Perhaps you should try some spelling variations:
hang lai » hang tai, hang hai, hang loi
ban hang » ngan hang
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
lai cua » dai cua, hai cua, lai chau
dua ban » dia ban, cua ban, qua ban
cac dua » cach dua, cac qua, cac du
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
y nang » ky nang, ly nang, v nang
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y nang ((x hoi) or (o hoi)). ((hieu ve) OR (hieu va)) cac dua ban hang lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((x hoi) OR (o hoi)). ((hieu ve) OR (hieu va)) cac dua ban hang lai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang ((x hoi) or (o hoi)). ((hieu ve) OR (hieu va)) cac dua ban hang lai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((x hoi) or (o hoi)). ((hieu ve) OR (hieu va)) cac dua ban hang lai cua tre*.