Hi, my name is Matt S Rinc and as a multimedia pro and technical writer I can help you.
But please - can you explain more details what problem you are facing? Things like:
1. Fuzziness of image captions (text) below images when book is displayed in Android _________ (device, version, screen size etc), Windows ________, Mac _________ etc.
2. Number of captions/images to fix.
3. What process do you use to convert your source document (book) e.g. Word to downloadable format e.g. PDF, MOBI etc?
Then it's possible to establish the fix, time to implement it and work needed. Example (few exported pages) would help too.
Regards,
Matt