Look at the status line at the bottom of the main Calibre window.
How to decode
The version you are using
The
man himself
1028 is the filtered (search results?) count if in use << this make the list LOOK shorter
of nnnn books, is the count
of your entire library <<<< look at this
and the last is how many are selected
If the entire count is bad, then your use of a Shared drive has corrupted or lost those.
Google Drive DESTROYS the Calibre indexing. This is the worst of the use of a shared.
None are good (Read the Calibre FAQ) . It is not IF, but
WHEN it will bite you.