Perhaps you should try some spelling variations:
studies based » studies case, study based
paris history » prices history, banks history
reforms under » reform under
class history » crises history
past reforms » post reforms, port reforms, pct reforms
based paris » based parsers, based panels, based period
under class » gender class, upper class, order class

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( case studies based paris history ) or ( past reforms under class history ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( case studies based paris history ) OR ( past reforms under class history ))*.