That functionality that you describe, selective PDF content export to Excel, is simply not currently available in Acrobat. It would require a facility by which you would “show” Acrobat what parts of the PDF pages to export. This would be a non-trivial function to add and even to use.
My recommendation would be to go to whoever sent you the invoice and ask if their system can export either an Excel spreadsheet or even a .CSV text file of the transactions which could be easily opened and edited directly in Excel. You'd be surprised how many companies actually can provide data in such formats when simply asked.
- Dov