Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh lap » thanh san, phan lap, thanh hai
cua viet » ca viet, hoa viet, cua vat
va triet » va thiet, va trien, ve triet
hieu van » hieu va, thien van, lieu va
van cam » van nam, van lam, van cau
cam tuc » cam xuc, cam tu, nam thuc
tuc ban » thuc ban, truc ban, tu ban
cua tre » cua te, cuu tre, cua triet
bach ky » bac ky
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu bach ky nang o hoi. hieu van cam tuc ban thanh lap ((cua tre) or (((cua viet) or (va triet))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu bach ky nang o hoi. hieu van cam tuc ban thanh lap ((cua tre) OR (((cua viet) OR (va triet)))).
• Adding a wildcard symbol may retrieve word variants: vu bach ky nang o hoi. hieu van cam tuc ban thanh lap ((cua tre) or (((cua viet) or (va triet))))*.