Hi there, @shang06.

Let me guide you on creating expenses by vendor report in QuickBooks Online. You can run and customize a Transaction List by Vendor to show your preferred columns.

Here's how:

1. Go to Reports on the left menu.
2. Search for Transaction List by Vendor.
3. Change the date period to your preference.
4. Click the Filter button, then choose Transaction type and Expense as the type.
5. Click Columns.
6. Scroll down, look for the Account name (Transaction line items: Split account), and click the eye icon to show the category column.
7. You can click and drag the column to reorder it in your report.

After getting the report ready, you can memorize the report to access it easily in the future.

If you have further questions about running a report in QuickBooks Online, please let us know by posting below. I'm always here to guide you.