Re: Book progress bar doesn't show up.
@Rurimorikaare you talking about skills books? If you Sim has a higher skill than the skill book you are reading caters for, then you will not gain any further skill points/progress bar from that particular book. You need the next book in the 'series'. You will still be able to read the book using the "read" or "re-read" functions.
E.g. if you have a brand new Sim with no skills at all, and purchase the book 'Cooking Volume 1', you will gain skill until you reach Cooking level 4. After that, you will no longer gain any skill points from reading 'Cooking Volume 1'. You will need to purchase 'Cooking Volume 2' to continue gaining skill points.
Edit: detail