Hi,
Base on my research, persian is a right-to-left language. Please make sure your version of Office supports Persian font. Please also make sure the Persian font is installed on your system.
In addition, how did you convert the PDF file to Word? Through a convertor tool? If so, please also contact the convertor support and check if you have set the tool properly. You can also try to use another convertor tool to check the result.
Best Regards,
Steve Fan
TechNet Community Support
