Hello Honeydo1,
Do you mean there is spelling mistakes on the scanned image? IF so, you will need a form of OCR Software (optical character recognition), which takes the scanned document and makes it an editable text document on your computer again.
http://www.free-ocr.com/
http://www.freeocr.net/
Although I've never had a reason to do this task personally. I can definitely say with confidence this is the type of software solution you would need to address that. I used to do HP printer support and so I'm quite familiar with scanning and the software solutions available for this particular problem.