Hi,
There is no such feature in the mass action system.
So I suppose that what you're doing is that you've configured a mass action on the "order" data type with a filter on the order_product_code column and and action to export a CSV with columns you selected in it.
This mass action will export the data of the orders with this order_product_code corresponding for at least one product in the order.
I suppose that you're confused as to why the columns of the table order_column are repeated in the CSV and why you don't see the corresponding product in these columns.
That's because what the export does is an export of orders and not of "sales of a product" like you want.
So each row of the CSV is an order.
And then, for the columns of the order_product table, it will repeat them once for each product in the order.
So if you have ten products in the order that match with the filter, you'll get these columns ten times, and each time, you'll have the information of one product of the order in the columns.
So you will have the information of the product of the filter in the CSV, but not always in the same columns.
For one order it might be in order_product_code in another one, it might be in order_product_code_3 (because it's the third product in the order and not the first).
What you would need for your goal is a mass action on the order_product data type so that you would have one product of an order on each row of the CSV and in that case, you would have only one set of columns of the order_product table and the information of the product you're looking for would always be in the same column.
But I can't say much more as I don't know what columns you're exporting and what use you have for them.
If you're only interested for the email address of the users who purchased product X, then a mass action as described above will work just fine.
But if you want to get the quantity of product X in each order, then that would indeed not be suitable solution.