You can see the invoices an inventory item is commited on from the inventory screen.
To open an inventory item, click inventory then inventory again to open the browsing inventory screen
enter the info in the search to find the inventory item you are looking
example seen below and then double click to open the inventory item
then click on functions, and then show committed
if you right click and choose field chooser you can drag and drop the invoice number to the column heading like shown below