At the end of the second canto, Śaunaka Ṛṣi asked Suta Goswami about the activities of Vidhura after leaving the palace, being offended by Duryodhana. Suta Goswami answers that Pariksit Maharaja asked the same question to Sukadeva Goswami after hearing the explanation of the Catuh-sloki Bhagavatam given in chapter 2.10, and thus proceeds in narrating it.
The third and fourth cantos of the Srimad Bhagavatam are centered around the conversation of Vidhura and Maitreya. All the pastimes narrated there, including the pregnancy of Diti and the birth of Hiranyaksa and Hiranyakashipu, the pastime of Kardama Muni and Devahuti, the instructions of Lord Kapila, Daksa offending Lord Shiva and Sati leaving her body, Prthu Maharaja milking the Earth and so on, are part of this discussion.
Srimad Bhagavatam #18: Vidhura meets Uddhava