Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban hang » ngan hang
cham duc » cham soc, pham duy, phan duc
hieu van » hieu va, thien van, lieu va
mai hoi » mai khoi, dai hoi, lai hoi
sang ky » sang kyo, dang ky, tang ky
hang vi » hang va, hanh vi, hang di
tu sang » thu sang, tu san, tu lang
me hoi » le 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 sang ky nang ((me hoi) or (mai hoi)). hieu van ((cham duc) OR (pham duc)) ban hang vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sang ky nang ((me hoi) OR (mai hoi)). hieu van ((cham duc) OR (pham duc)) ban hang vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sang ky nang ((me hoi) or (mai hoi)). hieu van ((cham duc) OR (pham duc)) ban hang vi cua triet".
• Adding a wildcard symbol may retrieve word variants: tu sang ky nang ((me hoi) or (mai hoi)). hieu van ((cham duc) OR (pham duc)) ban hang vi cua triet*.