Perhaps you should try some spelling variations:
graph ramsey » graphs ramsey, frank ramsey
john roy » john ray, john roe, john leroy
john rob » john robb, john r.b, john roe
kwon roy » kwon o, kwon go, kwon ho
raja r » raja j, raja m

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 roy) OR (john rob)) ) OR ( ((raja r) OR (raja _)) kwon roy )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( graph ramsey ((john roy) or (john rob)) ) or ( ((raja r) OR (raja _)) kwon roy ))".
• Adding a wildcard symbol may retrieve word variants: (( graph ramsey ((john roy) or (john rob)) ) or ( ((raja r) OR (raja _)) kwon roy ))*.