Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban hanh » ban hang
chat duc » chat xuc, chat doc, chet duoc
cua tre » cua te, cuu tre, dua tren
duc ban » duc tan, duc van, dua ban
ve chat » va chat, van chat
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
sac ky » cac ky, sai ky
ma hoi » xa hoi, ma hoa, me hoi
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky nang ((ma hoi) or (mai hoi)). hieu ve chat duc ban hanh vi ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang ((ma hoi) OR (mai hoi)). hieu ve chat duc ban hanh vi ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky nang ((ma hoi) or (mai hoi)). hieu ve chat duc ban hanh vi ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang ((ma hoi) or (mai hoi)). hieu ve chat duc ban hanh vi ((cua tre) OR (cua triet))*.