Where did I make a mistake in the formula?

Question

Google Sheets

=QUERY({FILTER(B:B,A:A<>"Stand",A:A<>"Tyzhen")\FILTER(C:C,A:A<>"Stand",A:A<>" Tizhen")},"select Col1/Col2",0)

Answer 1

=QUERY({FILTER(B:B,A:A<>"Stand",A:A<>"Tyzhen"),FILTER(C:C,A:A<>"Stand",A:A<>" Tizhen")},"select Col1/Col2",0)