sum distinct count

Hello 

I need help creating a graphic, I need to apply distinct count for two tables and I need to sum the results . 

I created the first measura and it´s workign fine, but I need to sum data to this measure from a differnt table and don{t know how to do it as the distinct count works for a specific table. I tried to add the second condition/distinct count BUT is not allowed, If I used them separate they work fine, I just need combine the 2 expressions from 2 different tables. 

Thnal you in advance.