Perhaps you should try some spelling variations:
"spanish colonial workers' party" » "british colonial workers' party", "spanish colonial borders' party", "spanish colonial powers' party", "spanish colonial worlds' party"
"spanish social workers' party" » "polish social workers' party", "swedish social workers' party", "spanish social work' 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 workers' party\") OR (\"spanish colonial workers' party\"))".
• Removing quotes may allow a broader search: (( spanish social workers' party ) OR ( spanish colonial workers' party )).
• Adding a wildcard symbol may retrieve word variants: (("spanish social workers' party") OR ("spanish colonial workers' party"))*.