Downloaded book in Greek with no searchable text

[Cyan_Dragon_13]

Ι recently bought a series of books in Greek which all have the same problem. One for example will do:

The name is: Εικονογραφημένον Βοτανικόν - Φυτολογικόν Λεξικόν: Τόμος Α΄

The link is: https://play.google.com/store/books/details/...

Τhe problem is as I will describe you. I can open and read the book(s) online and use as well the very useful search tool through the book (and this is really useful because it is a dictionary and what is more useful in a dictionary than a search faculty). So far so good.

But when I am downloading the books in my laptop and run it through ADE (adobe Digital Editions) the search is not available and this is very frustrating. (It does not appear it have any text, only image).

I am using windows 7  (home edition x64) and ADE to run my downloaded books.

Thanks in advance.

Nikolaos