Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
hieu van » hieu va, thien van, lieu va
hang lai » hang tai, hang hai, hang loi
ban hang » ngan hang
tham duc » tham du, than duc, thach duc
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
su sach » so sach, vu sach
lai va » loai va, mai va, dai va
x hoi » o 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: su sach thu nang ((x hoi) OR (xa hoi)). hieu van ((tham duc) or (pham duc)) ban hang lai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thu nang ((x hoi) OR (xa hoi)). hieu van ((tham duc) OR (pham duc)) ban hang lai va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thu nang ((x hoi) OR (xa hoi)). hieu van ((tham duc) or (pham duc)) ban hang lai va triet".
• Adding a wildcard symbol may retrieve word variants: su sach thu nang ((x hoi) OR (xa hoi)). hieu van ((tham duc) or (pham duc)) ban hang lai va triet*.