Perhaps you should try some spelling variations:
"card based working paper" » "card base working paper", "card based parking paper", "card basic working paper", "land based working paper", "carbon based working paper"
"world word working papers" » "world world working papers", "world work working papers", "world works working papers"

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: "((\"card based working paper\") OR (\"world word working papers\"))*".
• Removing quotes may allow a broader search: (( card based working paper ) OR ( world word working papers ))*.