Its not in version 9 anymore, at least as far as I can tell. There may be a note on it somewhere in the admin guide for 9. but I don't know as I haven't looked through all of it.
But, there are some options available to you. You may not like them, at least compared to the way it was under version 8.x, but you can do one of these 2 things-
• Export to csv, then open in Excel and print your Excel file to PDF
• While you have your search results up on screen, change the Show menu to "All", then choose Print and on the Print menu choose to save as a PDF.
The nice thing here is that Casper Suite 9 does a great job of removing all the extraneous UI stuff when printing what you see on screen and only giving you the content. Check it out and I think you'll be pleasantly surprised with that.
While neither of these are as pretty or convenient as the old PDF reports, they can at least get you a PDF of the search results, and maybe that's good enough?
Edit: regarding the second option, forgot to mention that you may need to change the scale in the print dialog to get all your shown columns to be on a single page width, depending on how many columns you have showing.