Hi, 

We can make changes in the Purchase Order template to do that for that follow the steps below:

1) Go to general settings

2) Click on "Activate developer mode (with assets)"

3) Now you will find some new menus in the General Settings, You will find a new menu Technical. Click on Reports under the Technical menu.

4) Now search for Purchase Order. and select the record, and inside it, you will see a smart button "QWeb Template" inside the record. Click on it.

5) In that you will see some records select the record with the view name "report_purchaseorder_document"

6) Now search for the code "<td id="product">

<span t-field="line.name"/>

</td>"

7) Now change that to "<td id="product">

<span t-field="line.product_id.name"/>

</td>"

8) Now Save the record and you will see the Name changes in the report. And you need to be careful while doing this because the modification

You make will be permanent and it is not possible to und the edit. SO make sure you change just the code which is mentioned above.