Nebuchadrezzar - A more correct way of spelling the name than Nebuchadnezzar.
According to all his wondrous works - The king and his envoys expected some such answer as Isaiah had given on a former occasion Isaiah 37:6.
Related Commentaries of Jeremiah 21:2
Jeremiah 21:2
2 Enquire, I pray thee, of the LORD for us; for Nebuchadrezzar king of Babylon maketh war against us; if so be that the LORD will deal with us according to all his wondrous works, that he may go up from us.