Perhaps you should try some spelling variations:
"spanish social worker' party" » "polish social worker' party", "swedish social worker' party", "spanish colonial worker' party", "spanish social work' party", "spanish social world' party", "spanish social market' party"
"spanish social workers' party" » "polish social workers' party", "swedish social workers' party", "spanish colonial workers' party", "spanish social work' party", "spanish social works' party", "spanish social worlds' party", "spanish social markets' party"

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"spanish social worker' party\") OR (\"spanish social workers' party\"))".
• Removing quotes may allow a broader search: (( spanish social worker' party ) OR ( spanish social workers' party )).
• Adding a wildcard symbol may retrieve word variants: (("spanish social worker' party") OR ("spanish social workers' party"))*.