Exporting PDF to word to make words searchable

Greetings,

I recently started a class online for college and the textbook was given from the college as PDF documents. The textbook is all images though and thus I cannot search the document for key words. I purchased the Export PDF function because it said it could export to word document and make the words searchable. After I exported the PDF file, the word document is the exact same as the prior pdf file, with the words not searchable.

What can I do to make the words in the image searchable?

Thank you,

Adam Budde