Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban hang » ngan hang
cham duc » pham duc, pham duy, phan duc
hieu van » hieu va, thien van, lieu va
mai hoi » mai khoi, dai hoi, lai hoi
sach ky » sac ky, sach y, sach ty
hang vi » hang va, hanh vi, hang di
tu sach » thu sach, su sach, te sach
ma hoi » xa hoi, ma hoa, me hoi
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang ((ma hoi) or (mai hoi)). hieu van ((cham duc) or (cham soc)) ban hang vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((ma hoi) OR (mai hoi)). hieu van ((cham duc) OR (cham soc)) ban hang vi cua triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((ma hoi) or (mai hoi)). hieu van ((cham duc) or (cham soc)) ban hang vi cua triet*.