Perhaps you should try some spelling variations:
general equations » integral equations
general relative » general relation, general relations, general operative
general relating » general relations, general relation, general reading
"general relativity" » "general relatively"

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: (("general relativity") OR ("((((((general relative) OR (general relating))) or (general equations))ly) or (((((general relative) OR (general relating))) or (general equations))))")).
• Removing quotes may allow a broader search: (( general relativity ) or ( ((((((general relative) OR (general relating))) or (general equations))ly) or (((((general relative) OR (general relating))) or (general equations)))) )).
• Adding a wildcard symbol may retrieve word variants: (("general relativity") or ("((((((general relative) OR (general relating))) or (general equations))ly) or (((((general relative) OR (general relating))) or (general equations))))"))*.