Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
hieu van » hieu va, thien van, lieu va
van tham » van thanh, van tuan, van chat
tham duc » pham duc, tham du, than duc
ban hanh » ban hang
hanh lai » hanh lam, hanh tai, thanh lap
va triet » va thiet, va trien, ve triet
su sach » so sach, vu sach
duc ban » duc tan, duc van, dua ban
lai va » loai va, mai va, dai va
x hoi » xa hoi, x ho, 5 hoi
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach thu nang ((x hoi) OR (o hoi)). hieu van tham duc ban hanh lai va triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thu nang ((x hoi) OR (o hoi)). hieu van tham duc ban hanh lai va triet".
• Adding a wildcard symbol may retrieve word variants: su sach thu nang ((x hoi) OR (o hoi)). hieu van tham duc ban hanh lai va triet*.