Perhaps you should try some spelling variations:
sach van » sach han, sach va, bach van
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
dua ban » dia ban, cua ban, qua ban
hanh va » hang va, hanh vi
su viet » so viet
ve cac » va cac, vien cac
ban x » ban xu, ban _, ban 1
x hoi » xa hoi, o hoi, x ho

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 van ban x hoi. hieu ve cac ((duc tan) or (dua ban)) hanh va su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach van ban x hoi. hieu ve cac ((duc tan) OR (dua ban)) hanh va su viet*.