Perhaps you should try some spelling variations:
ve triet » va trien, su triet
sach thu » sach thue, sach thieu, sach tham
hanh lam » thanh lap, hanh kem, hanh va
hanh lai » hanh tai, thanh lap, thanh loi
tham duc » pham duc, tham du, than duc
van tham » van thanh, van tuan, van chat
hieu van » hieu va, thien van, lieu va
thu nang » thi nang, thu hang, thu bang
su sach » so sach, vu sach
co hoi » co hoc, co loi
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: su sach thu nang ((x hoi) or (co hoi)). hieu van tham duc tan ((hanh lai) OR (hanh lam)) ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thu nang ((x hoi) OR (co hoi)). hieu van tham duc tan ((hanh lai) OR (hanh lam)) ve triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thu nang ((x hoi) or (co hoi)). hieu van tham duc tan ((hanh lai) OR (hanh lam)) ve triet*".