Question: Jeremiah (49:33) predicts that humans will never again live in Hazor, but will be replaced by dragons. But people still live there and dragons have never been seen.
Response: The word "dragons" comes from a 400-year-old English translation of the Bible, called the KJV, or King James Version. In the Hebrew language, the word is tanniyn, and it has been translated into English in a variety of ways, such as "whale," "serpent," "venemous snake," "monster," or "jackal."
The word conveys the idea of a frightening animal, either because the animal is a predator, or because the animal is very large, or because the animal is both. And, apparently, the English translators during the early 1600s understood this and that is why they chose the English word "dragons" as a way to translate the meaning of tanniyn into the English language.
Many modern English translations, including the New King James Version, translate the Hebrew word tanniyn into English as "jackals."
As for whether people are still living in Hazor, it should be understood that the Hazor mentioned in Jeremiah 49:33 is not the town of the same name in Israel. In fact, this is made clear in Jeremiah 49:28, where Hazor is identified as the "kingdoms of Hazor," which Nebuchadnezzar, the king of Babylon, had attacked. The exact location of the ancient kingdoms of Hazor are no longer known.