Irregular space between letters (PDF file to any other format)

Hello.
I search a lot about this problem but I didn't found a solution to my case. So I'm here humbly asking for help, please.
English is not my first language so I apologize in advance for possible mistakes in my messages.

I'm trying to convert a PDF file to any ebook format, or any format really that later on I can convert into ebook.
But everything gives the same result: irregular space between letters.
I tried PDF to .docx, PDF to htmlz, PDF to epub, PDF to mobi with Calibre and no luck.


[Attachment deleted: Copyright violation - Moderator]