Perhaps you should try some spelling variations:
functional relationships » function relationships, function relationship
spatial relationships » spatial relations, animal relationships
social relationships » social relations

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: ((((social relationships) OR (functional relationships))) OR (spatial relationships)).
• Adding a wildcard symbol may retrieve word variants: ((((social relationships) or (functional relationships))) or (spatial relationships))*.