Perhaps you should try some spelling variations:
thieu bang » thien bang, thieu khang, thieu quang
ve triet » va trien, su triet
hanh lai » hanh lam, hanh tai, thanh lap
tan hanh » tan thanh, tang hanh, toan hanh
tham duc » pham duc, tham du, than duc
hieu van » thien van, lieu va, hieu ve
hieu va » lieu va, hieu qua
su sach » so sach, vu sach
lai ve » loai ve, lai va, la ve
o hoi » co hoi, o hoc, o hai
x hoi » xa 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 thieu bang ((x hoi) or (o hoi)). ((hieu van) OR (hieu va)) tham duc tan hanh lai ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thieu bang ((x hoi) OR (o hoi)). ((hieu van) OR (hieu va)) tham duc tan hanh lai ve triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thieu bang ((x hoi) or (o hoi)). ((hieu van) OR (hieu va)) tham duc tan hanh lai ve triet*".