The next prerelease has a new function to extract text from only a part of the page. So like in example you can define an area (e.g. column) for text extraction.
In our example app above, we extract each quarter of the page on its own. If you have to extract text from multi column pages regularly, you could define the rectangles for left/right columns and get text.
(this feature requires DynaPDF Pro and is available for FileMaker, Xojo and Real Studio)