1 Nephi 5:13

and also the prophecies of the Holy prophets, from the beginning, even down to the commencement of the reign of Zedekiah; and also many prophecies which have been spoken by the mouth of Jeremiah.

They also had the prophecies of the holy prophets from the beginning until King Zedekiah started ruling. They also had many prophecies that Jeremiah spoke.

The plates included prophecies from the holy prophets, from the beginning up to Zedekiah’s reign, including many prophecies spoken by Jeremiah.