Show List of Invoices Attached to a Partner in the Partner Record

This can be accomplished through a saved search and a sublist.

First part is to create a Saved Search.

     1. Navigate to Lists > Search > Saved Searches > New.

     2. Select Transaction.
     
     3. Provide a Search Title.

     4. In the Criteria tab > Standard subtab, add a filter Type is Invoice.

     5. In the Results tab > Columns subtab, add required fields.

     6. In the Available Filters tab, add the Partner field.

     7. Click Save.


Second part is to create a Sublist.

     1. Navigate to Customization > Forms > Sublists.

     2. Click the Entity tab.
     
     3. Select the saved search created in the Search field.

     4.  Provide a Label.

     5.  In the Tab field, select the tab where to show the sublist.

     6.  Check Partner field.

     7.  Click Save.