Perhaps you should try some spelling variations:
industrial revolution » industrial relations, industrial production
industrial relation » industrial relations, industrial location, industrial revolutions
revolution krieg » revolution during, revolution priest, revolution series
relation system » relations system, relations systems, regulation system

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: (( industrial revolution krieg. ) OR ( industrial relation system. ))~.
• Adding a wildcard symbol may retrieve word variants: (( industrial revolution krieg. ) or ( industrial relation system. ))*.