Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
ban hang » ngan hang
ve triet » va trien, su triet
hieu ve » hieu van
hieu va » lieu va, hieu qua
cam duc » cam xuc, cao duc, pham duc
duc ban » duc tan, duc van, dua ban
hang ve » hang va, hanh ve, hang ke
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
o hoi » co hoi, o hoc, o hai
ve ve » de ve, va ve, ke ve

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach v nang ((xa hoi) or (o hoi)). ((hieu ve) OR (hieu va)) cam duc ban hang ve ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach v nang ((xa hoi) OR (o hoi)). ((hieu ve) OR (hieu va)) cam duc ban hang ve ve triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach v nang ((xa hoi) or (o hoi)). ((hieu ve) OR (hieu va)) cam duc ban hang ve ve triet*".