Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van phat » va phat, van chat, van phan
phat duy » pham duy, phat huy, phan duy
ban hang » ngan hang
cua viet » ca viet, hoa viet, cua vat
mai hoi » mai khoi, dai hoi, lai hoi
duy ban » uy ban, duy van, duy can
hang vi » hang va, hanh vi, hang di
tu can » tu ban, tu cac, thu canh
can ky » van ky, dan ky, ban ky
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 can ky nang ((me hoi) or (mai hoi)). hieu van phat duy ban hang vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu can ky nang ((me hoi) OR (mai hoi)). hieu van phat duy ban hang vi cua viet.
• Adding a wildcard symbol may retrieve word variants: tu can ky nang ((me hoi) or (mai hoi)). hieu van phat duy ban hang vi cua viet*.