OR operator in reports - How to draw a Participants report where A OR B?
What you're asking isn't supported with CiviReport, unfortunately.

You have a couple of alternative options:


You can build a Smart Group that meets your criteria, then filter by the Smart Group.  However, I'm not sure what the current state of relative date filters and smart groups is these days, so this may not work.
You can integrate a more advanced reporting engine like Hitachi Vantara or Tableau.
If you're using Drupal as your CMS, you can build a View with CiviCRM integration to provide the report you need.