how to create report with PRODUCT in tickets

how to create report with PRODUCT in tickets

Hello, 
We use the "PRODUCT" field in ticket forms , and I would like to create a report to summarize how many ticket we had for each product. 
But the issue i'm facing is that i don't find "Products" in the available fields for ticket : 
 

Did i missed something ? 

/BR
Stéphane