As i told earlier that, these images are scanned images of PDF files so it is behaving like images.
I have used GetVisibleText method to get text from these files and there are lots of issues with this method (like fetched texts formating is depending on location of page in Acrobat window) every time page is zoomed or page is scrolled a little bit text fetched form file will entirely different.
Due to this problem i am unable to get a fix format text(like if zoom level or scroll position is changed earlier line 1 divide in two lines or if a line come at 5 th place with zoom 100% it may come at 10 place with 101% Zoom or there may be some special character in place of it).
I *think* what you have is some sort of hard-copy document that has been scanned and saved as a PDF file, and therefore even Adobe Reader can't recognize the text? If so, I can't see how QTP would ever be able to recognise the text. You would need to run some sort of OCR software after scanning the document and *then* save it as a PDF, otherwise all you have is one big image.
OCR software would convert your scanned document into a text document (rather than one single scanned image). You would then simply convert the new text document into a PDF document as normal, and Adobe Reader / QTP would then be able to read the actual text from your PDF.