Hi my name is ***** ***** I will be the expert working with you today to help resolve your problem.
What app are you using to read ebooks Is it the Amazon App you are using on the Samsung Tab Or the Nook App?
If you are using a Google Playbook App.To remove a book, select the Menu button located alongside any item in your collection.Then choose Delete or remove from library.
or you can long press on the Book and choose Remove from Library when it appears.
other way is to connect the tablet to the computer using the usb cable and the follow the steps given below
To Delete them then via your computerFrom your computer, log in to Google Play Books (www.google.com/books works).-Click the "MyBooks on Google Play" towards the top of the page-Under each book you want removed, click the menu button beside the "Read" button and click "Remove from My Library"
Let me know if you have any difficulties.