Thanks for getting back to this thread, @LynB756. 

I'm here to clarify the steps provided by my colleague above to pull up the report with the list of all assemblies.

Let me show you how:

1. Go to the Lists menu, then choose Item list. 
2. Look for the item and select the Reports drop-down menu.
   
   
   
   
3. Choose QuickReport.
   
   
   
   
4. In the report, click the Customize button.
5. Find and select your inventory assembly to see the list showing all of the parts involved with your assembly.
   
   

For more info on how to add a filter to your report, feel free to view this article: Customize reports in QuickBooks Desktop.

Also, you can memorize reports in QuickBooks if you want the same settings of the customized report to be available for future use. This way, you do not have to go through the customization process again.

Keep me posted if you need more help managing your reports in QuickBooks. I'll be happy to lend a helping hand. Have a great rest of the day.