Hi Gustavo,
as I've understood you need a combination of a conditional block with a variable that checks parameter values.
Drag a new conditional block at the position where the list is.

Then go to variables.

You will need to create a boolean variable that returns yes only when both drop down boxes are filled. In my sample this looks like this:

Now back to the report page and assign the new variable to the conditional block. You'll get as many block instances as you have variable results. In this case on block for "Yes" and one block for "No".

Select the two blocks and place the according content into them. I dragged the following stuff into the "No" block:

Then the Yes block looks like that:

Of course you can also use other variable types with more instances than just Yes/No - that's op to you.
Any further questions?
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Robert Dostal
Team Leader BI
GEMÜ Gebr. Müller Apparatebau GmbH & Co. KG
Ingelfingen
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