1, not software;

2. That's because the file (paper or book) you opened was obtained in the form of picture scanning, not by word file conversion. The text recognition function of CAJ software doesn't work for this kind of documents, and pdf files are similar, so text recognition is not available.

I suggest you download a pdf file with the same name or go to other websites. You can only try your luck, but there is no way to scan pictures in CAJ or pdf format.