Perhaps you should try some spelling variations:
"cable telegraphy" » "all telegraphs", "early telegraph", "le telegraphe"
"mayo telegraph" » "mails telegraph", "random telegraph", "marine telegraph"
"a telegraph" » "a telegraphe", "_ telegraph", "2 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: (("cable telegraphy") OR ((("mayo telegraph") OR ("a telegraph")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"cable telegraphy\") or (((\"mayo telegraph\") OR (\"a telegraph\"))))".
• Removing quotes may allow a broader search: (( cable telegraphy ) or ((( mayo telegraph ) OR ( a telegraph )))).
• Adding a wildcard symbol may retrieve word variants: (("cable telegraphy") or ((("mayo telegraph") OR ("a telegraph"))))*.