Perhaps you should try some spelling variations:
sach van » sach han, sach va, bach van
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
hanh ki » hanh vi, hanh ky, hanh kien
dua ban » dia ban, cua ban, qua ban
duc ban » duc tan, duc van, duc man
su viet » so viet
hieu ve » hieu va
x hoi » xa hoi, o hoi, x ho
ban x » ban xu, ban _, ban 1
ki su » ky su

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: tu sach van ban x hoi. ((hieu ve) OR (hieu van)) cac ((duc ban) OR (dua ban)) hanh ki su viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach van ban x hoi. ((hieu ve) OR (hieu van)) cac ((duc ban) or (dua ban)) hanh ki su viet~".
• Adding a wildcard symbol may retrieve word variants: tu sach van ban x hoi. ((hieu ve) OR (hieu van)) cac ((duc ban) or (dua ban)) hanh ki su viet*.