Perhaps you should try some spelling variations:
"graph ramsey john roe" » "graphs ramsey john roe", "frank ramsey john roe", "graph ramsay john roe", "graph casey john roe", "graph ramsey john rose", "graph ramsey john rowe", "graph ramsey john roger"
"graph ramsey john rolle" » "graphs ramsey john rolle", "frank ramsey john rolle", "graph ramsay john rolle", "graph casey john rolle", "graph ramsey john rose"
"raja m mohon roy" » "raja m cohen roy", "raja m mon roy", "raja m mohan roy", "raja m moxon roy", "raja m morton roy", "raja _ mohon roy", "raja j mohon roy", "raja r mohon roy"

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: (((("graph ramsey john roe") OR ("graph ramsey john rolle"))) OR ("raja m mohon roy")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"graph ramsey john roe\") OR (\"graph ramsey john rolle\"))) or (\"raja m mohon roy\"))".
• Removing quotes may allow a broader search: (((( graph ramsey john roe ) OR ( graph ramsey john rolle ))) or ( raja m mohon roy )).
• Adding a wildcard symbol may retrieve word variants: (((("graph ramsey john roe") OR ("graph ramsey john rolle"))) or ("raja m mohon roy"))*.