Use the bw_pdf shortcode to display the PDF files which are attached to a specific post ID.
If you have attached PDF files to another post then you can display them by using the
post_parent parameter to identify the post that they’re attached to.
[bw_pdf post_parent=5218 titles=n]
Here we display links to the PDF files which are attached to the original help for the [bw_pdf] shortcode.