How to decode a pdf textbook so that you can use the search function?

Question

PDF

There is a pdf file - this is a tutorial, but the file itself is encoded. When you open it through a Word, strange characters are displayed there. How to decode a file so that you can use the search function?

Answer 1

pdf is the final format and it cannot be opened just like that in word
, it can be opened in pdf editor but editing is limited
search is possible if there is a normal text layer from ordinary pdf readers