Not really (without looping through the orders in PHP which would be very slow). That's the point of having separate SKUs.
SKU stands for "Stock Keeping Unit", and so by definition if you want to keep track of how many of each item was purchased you should use separate SKUs. In fact Store already provides built in reports to display how many of each SKU you have sold.
The "Single SKU modifier" was really only added in Store 1 to avoid people having to make up lots of SKUs if they didn't need them. But now in v2 SKU names are no longer required fields, so there is not much need for the single SKU modifier any more, you can just create them as regular multi-SKU products, leave the SKU names blank, and get the advantages of separate reporting etc.