Wix Digital downloads

Hi, i sell a lot of ebooks each day and im getting a lot of people who can simply share the product to their friends from the email they receive to download the digital products, i want to make this more secure so no one can share the PDF file, any ideas?

Yes i posted a similar query here..

Basically, there is a Download button in the member’s profile after a user orders a digital item.

I want to be able to add an OAuth-tied code to the Download button (similar to main page buttons), so that only the purchaser receiving that download button in his profile can access whatever’s behind it (link, file, etc.).

Also i want to change the word ‘Download’ to something else.