Use the Content panel to correct reflow problems in a PDF that can’t be corrected by using the Touch Up Reading Order tool. Because you can damage a PDF by editing content objects, make sure that you’re familiar with PDF structure before you change anything. For comprehensive information about PDF structure, see the PDF Reference Sixth Edition: Adobe Portable Document Format Version 1.7, on the PDF reference page (English only) of the Adobe website.
The Content panel provides a hierarchical view of the objects that make up a PDF, including the PDF object itself. Each document includes one or more pages, a set of annotations (such as comments and links), and the content objects for the page. The content objects consist of containers, text, paths, and images. Objects are listed in the order in which they appear on the page, like tags in the logical structure tree. However, PDFs don’t require tags for you to view or change the object structure.