Hello there, @PozoRick.

It's great to see you here today. I can help you customize a report to show customers in a range of activity. 

Reports in QuickBoooks Online can be customize according to the information needed. You can run and customize the Transaction List by Customer to do that.

I'll show you how:

1. Click Reports.
2. On the search field, enter Transaction List by Customer.
3. Update the Report period.
4. Click Run report to refresh the information.

To have a better view of the customer list, you could export the report to Excel and customize it from there:

1. Click the Export icon (see screenshots attached).
2. Choose Export to Excel.
3. Click OK on the small window.
4. On the Excel file, click the Filter button.
5. Click the first column drop-down. 
6. Select the customer names.
7. Click OK.

There you have it. Let me know if you need more help with reports, and I'll jump right back.