Right! It would have been stunning if it tried to aquire every book published in every language... Though I suppose if certain books are imported and sold, then they would show up in this library
It doesn't even have every book published in the UK, because there are a lot of books, especially at the beginning of the printing press period, which does not exist in any known copies anymore.
Not to mention that the policy of collecting ephemera is a relatively new one, so most older ephemera doesn't exist in its collections either.