Hi there, @arthurb!
You can pull up your Profit and Loss Detail report and filter it with the specific accounts of your choice. I'm here to help you accomplish this.
Instead of customizing your general Profit and Loss report, you can pull up your Profit and Loss Detail report and customize it.
Nevertheless, here's how you can pull up and customize your Profit and Loss Detail report:
Once completed, you'll surely be able to filter your Profit and Loss Detail report with only specific accounts you've chosen.
In addition, here's an article you can read to learn more about customizing your Profit and Loss report: How to Customize your Profit and Loss Report?
Lastly, you can save this customized report for easy-viewing when needed in the future. Just click the Save customization button, then go to the Custom reports tab to find this report.
Should you need additional help in customizing your Profit and Loss report? Just leave it in the comment section below, I'll be always around to help you out.