Perhaps you should try some spelling variations:
dao nang » cao nang, da nang, dai nang
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
thuc ban » thuoc ban, thuc dan, thu ban
ban hanh » ban hang
hanh dai » hanh tai, hanh dao, vanh dai
su sach » so sach
vu sach » vu bach, vu khach
mai hoi » mai khoi, dai hoi, lai hoi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) dao nang ((xa hoi) OR (mai hoi)). hieu van nam thuc ban hanh dai cua vat~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (vu sach)) dao nang ((xa hoi) or (mai hoi)). hieu van nam thuc ban hanh dai cua vat~".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (vu sach)) dao nang ((xa hoi) or (mai hoi)). hieu van nam thuc ban hanh dai cua vat*.