The calculated distance (air line) between Nowe Miasto Lubawskie and Kielce is approximately 182 miles respectively 292 kilometers.
By car or train, the actual journey to Kielce is certainly longer, as only the direct route (as the crow flies) between Nowe Miasto Lubawskie and Kielce has been calculated here.
Air line (approximately)
292 kilometers
158 nautical miles