Formula to select certain people only

I have a spresdsheet in google sheets and use the following formula

=QUERY('Main Data'!A2:U,"select B, sum(J), sum(E),count(E), sum(F), count(F), sum(G), count(U), WHERE A IS NOT NULLAND O>= DATE """&text(H2,"yyyy-MM-dd")&""" AND O<= DATE """&text(H3,"yyyy-MM-dd")&"""    group by Border by sum(J) desc

The problem is that there are 10 x sales peoples names in column B, and I only want to select certain people, but I cant get it to work.