I need to show more then one value in the expression - pivot table

[#1]

I have a pivot table with 2 dimensions and 1 expression.

When I have more then one value to show in the expression it is appering as null.

It something like this I have the dimension School and the other dimension is type of events in my expression is events so when I have two events of the same type it is showing nothing but I need to show all of them

[#2]

The concat worked but it is not considering the filters.

[johnw]

OK, looks like the School-={...} also excludes null, and then it just got confused when I gave it a second set expression for School.  So this.

concat({<Event_type={'fundraising','prom'},School-={'PINHEIRO','ESMERALDO'},Event*={"*"}>} distinct School & ' - ' & Event_Description, '/')

[#4]

John. Thank you so much for your help.