You're welcome. It's our pleasure to help, @jenuneekor.

You can check all those refund receipts that you've created for your customers using the Advanced Search option. You'll just have to click on the Magnifying icon at the top and click on the Advanced Search option. 

Just set the filter for Refunds and the specific customer to view the receipts associated with that profile. 

Check this article for more information: Search for transactions. This article can tell you more about how to record a customer refund in QuickBooks Online.

I'm always here to provide help and answer any questions that you may have with your transactions. Have a great rest of the day!