Perhaps you should try some spelling variations:
global telegraph » global demography, global tomography, global graph
early telegraph » mails telegraph, early typography, early tomography
delay telegraph » solar telegraph, delay tomography, aerial telegraph
der telegraph » der telegraphen, der telegraphie, _ telegraph

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: ((early telegraph) OR (((((delay telegraph) OR (global telegraph))) OR (der telegraph)))).
• Adding a wildcard symbol may retrieve word variants: ((early telegraph) or (((((delay telegraph) or (global telegraph))) or (der telegraph))))*.