Hmm, I haven't used libpdf to know enough, but just from glance through its documentation, it seems libpdf is more suitable for creating and reading PDF files. If this is correct, then it'll be missing the bridge to converting the read content of the PDF file to a Word document
I see a couple of things called libpdf...lib-pdf and libpdf++. One generates pdfs programmatically. The other parses pdfs, but generates only images. Maybe you meant something else?