Reports > View By List
When you run a "Non-Opens" report, it will show you all of the subscribers who have not opened any campaign you sent within the date range your selected.
Step 1.
Go to "Reports > View By List".
Step 2.
Select your "Date Range".
Step 3.
Select the list you want to run the report for.
Step 4.
In the "Report Type" drop down box, choose "Non-Opens Report".

Step 5.
Click on the "Show Report" button.
Once the report is generated, you can click on the number to pop-up a window to display the subscribers. You can export that list from the pop-up window.