The calculated distance (air line) between Osterholz-Scharmbeck and Bochum is approximately 138 miles respectively 222 kilometers.
By car or train, the actual journey to Bochum is certainly longer, as only the direct route (as the crow flies) between Osterholz-Scharmbeck and Bochum has been calculated here.
Air line (approximately)
222 kilometers
120 nautical miles