I submitted for CME credits across multiple courses, but it only produced a single PDF?

Yes.  Every claim is more or less a single "action" wherein a group of earned credits are claimed and certificate(s) are produced.

If you claim multiple CME credits across multiple course titles, your single PDF will include multiple certificates, one for each course with the appropriate number of CME credits claimed for that course.  

Under each "certificate" within your PDF claim document, you'll find the topic items included in that course's certificate.

Simply print or "save as" the pages you need from the PDF in such cases.