Lightroom :: Add Images From Collection After The Book Is Saved?

I prepared a rough draft of a book and saved it with the tab on the right hand top of the main screen. Unfortunately, I saved it with the option of only saving the used images from the original collection. Later I brought up the draft book and tried to add some additional images, but see that only the images already used in the book are available on the image strip at the bottom.  I need to get other images which are in the original collection.  Is there any way to do this?  If not, is there a way to save the entire format of the book and then start over with the same format but with the original full collection as the source of images in the bottom strip?