Here are methods to make a PDF searchable for free.
- Using Google docs
- Upload your PDF to google drive.
- Right click on the PDF and open with google docs.
- This converts the PDF to text format.
- Now you can search for text within this PDF.
- You can also use an online services
- https://www.sandwichpdf.com/
- http://www.paperfile.net/
- https://www.onlineocr.net/
- https://www.sodapdf.com/ocr-pdf/
- https://ocr.space/