Perhaps you should try some spelling variations:
cam duc » cam xuc, cao duc, pham duc
hang di » hang doi, hang vi, hang dien
hieu ve » hieu va, hieu van
duc ban » duc tan, duc van, dua ban
tu san » thu san, tu ban, tu can
ve cam » ve cham, ve cac, va cam
cua cu » cua chu, cua cau, cua su
san ky » sang ky, van ky, dan ky
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: tu san ky nang ((x hoi) or (o hoi)). hieu ve cam duc ban ((hanh vi) or (hang di)) cua cu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu san ky nang ((x hoi) OR (o hoi)). hieu ve cam duc ban ((hanh vi) OR (hang di)) cua cu.
• Adding a wildcard symbol may retrieve word variants: tu san ky nang ((x hoi) or (o hoi)). hieu ve cam duc ban ((hanh vi) or (hang di)) cua cu*.