Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
tham thuc » nham thuc, pham thuc, tam thuc
thanh hoa » thanh pho
thuc ban » thuoc ban, thuc dan, thu ban
su triet » su viet, su tien, ve triet
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
ve tham » va tham, ve cham, vi tham
so dac » so dan
dac ky » cac ky, dan ky, sac ky
ma hoi » xa hoi, ma hoa, me hoi
hoa su » hoa lu, hoa si, hoa du

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

• Performing a fuzzy search may retrieve terms with similar spellings: so dac ky nang ((ma hoi) OR (mai hoi)). hieu ve tham thuc ban thanh hoa su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so dac ky nang ((ma hoi) OR (mai hoi)). hieu ve tham thuc ban thanh hoa su triet".
• Adding a wildcard symbol may retrieve word variants: so dac ky nang ((ma hoi) OR (mai hoi)). hieu ve tham thuc ban thanh hoa su triet*.