How do I create a report for a specific expense category but include sales taxes paid for items only in that category?

Hi there,

Welcome to the Community. I'm glad to learn you're using QuickBooks  to help streamline your business. I'll be happy to steer you on the right path so you can continue being amazing at managing your business. 

QuickBooks is an easy-to-use program that simplifies the way you handle your accounting. The report you've described isn't available in QuickBooks. I can see the benefit of having access to this report and I encourage you to send feedback about this to our engineers. To do this, click on the Help menu and look for Send Feedback Online. I encourage you to check out this article here that goes over the: Reports included in your QuickBooks Online subscription. 

Let me know if this info helps. I'll be one message away in case you have additional questions.