Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
duc van » duc tan, duc manh, duc phan
hanh di » hanh vi, hanh de, hang di
su dai » sau dai, si dai, su tai
dai ky » dan ky, dai ly, sai ky
ma hoi » xa hoi, ma hoa, me hoi
ve cac » va cac, vien cac
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su dai ky nang ((ma hoi) or (mai hoi)). hieu ve cac ((duc van) or (duc va)) hanh di cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su dai ky nang ((ma hoi) OR (mai hoi)). hieu ve cac ((duc van) OR (duc va)) hanh di cua triet.
• Adding a wildcard symbol may retrieve word variants: su dai ky nang ((ma hoi) or (mai hoi)). hieu ve cac ((duc van) or (duc va)) hanh di cua triet*.