Can longtails be picked up in PDF files?

I'm looking to get some additional terms ranking well for a PDF we have on our site. It ranks well for the title of the document but not for many terms after that. We attempted to support some terms and locations by adding a little bit of content with said terms but didn't want to make it look tacky. Some of the less competitive terms rank well.

Are they any other specific ways to capture longtails within a PDF file? Maybe a silly question but would using different anchor text backlinks help pull out some of these longtails?

Yes theoretically it can support longtails, just how many is the question and how many pages deep does the index go. So google will read the PDF file, I don't know if they're efficient at it, and they'll include pdf files info (titles, size). Not sure if it's the best way to include 200 pages of a manual or something since they generally don't index an entire pdf document.

Thanks dj. Im only talking about a 3-5 page document. I also don't know how well Google or other search engines index and read them. We did support it with some content and those terms seem to be ranking fine (non-competitive mind you) but I was wondering if adding some links with different keywords would help get more terms to rank the document.

I would not say that PDF's are particularly inferior as far as standards applied through the algorithm. In my industry for several high volume search terms PDFs rank quit high in the results, mostly from .gov sites.

So I know they have high ranking potential. Have you considered the advantages of converting them to HTML files and placing the actual PDF as a download link in a no-index folder?

The pdf FILE will rank because of the nature of the titles and perhaps the content. My questions was how far they drilled down into a lengthy document and if they treated the pages in a pdf files as the same as interior html pages on a web site. I haven't tested this.

Great replies, thanks guys.

I would have to look into the cost of converting them to an html file. One of the more popular ones on our site is a chart so I'm not sure what would be involved with converting it to an html file. I am hoping to acquire actual documents vs scanned images in the future. The only reason they are pdf's is b/c I wasn't sure how else to add a scanned document to the site.