The
Split Merged Output to Separate Documents topic in my
Mailmerge Tips and Tricks 'Sticky' thread at the top of this forum shows how to do that:
https://www.msofficeforums.com/mail-...ps-tricks.html. What you need to do, though is precisely specify the location of the content you want to use for the names (e.g. which paragraph and, perhaps, what portion of that paragraph) - which all depends on your merged output's layout.
Rather than splitting the document post-merge, it's probably better to do it during the merge. See
Send Mailmerge Output to Individual Files in the
Mailmerge Tips and Tricks 'Sticky' thread.