Hi @mauiceo !
Are you using Shopify’s email campaign tool, or have you got an app installed to send campaigns?
Just thinking that there are a few possible ways you could go about this.
If you use Google Analytics, you could use UTMs. This is a small piece of code you add to end of your shopping link - this will let you track when sales are made, and show what campaign they are linked to (for example, your reacquisition email campaign).
How this would look:
In your email campaign, just make a small edit to any links or buttons - add a code (like the below) to your store link. Don’t forget the question mark! 
E.g. ?utm_campaign=reacquisition
You might also want to see if these emails get in-store sales too.
In Marsello, you can see sales on your Shopify store that came from a particular email campaign or email automation. You can also connect your POS to see if the emails led to any in-store sales.
It depends on what tools you’re using and what you’re trying to achieve really! Happy to help where I can.
Alice