Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
vu khach » vu khanh, vu khac, vay khach
nam thuc » nam thuoc, am thuc, nam thu
thanh vi » hanh vi, thanh va, thanh ve
thuc ban » thuoc ban, thuc dan, thu ban
cua viet » ca viet, hoa viet, cua vat
hieu ve » hieu va, hieu van
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, v nang, may nang
ve nam » he nam, va nam, le nam
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: vu khach ((y nang) or (ly nang)) x hoi. hieu ve nam thuc ban thanh vi ((cua tre) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu khach ((y nang) OR (ly nang)) x hoi. hieu ve nam thuc ban thanh vi ((cua tre) OR (cua viet)).
• Adding a wildcard symbol may retrieve word variants: vu khach ((y nang) or (ly nang)) x hoi. hieu ve nam thuc ban thanh vi ((cua tre) or (cua viet))*.