Perhaps you should try some spelling variations:
learning inequality » earnings inequality, learning quality, measuring inequality
garding inequality » garding's inequality, earnings inequality, hardy inequality
warning inequality » earnings inequality, widening inequality, facing inequality

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: (( wage AND garding inequality ) OR ( wage AND ((warning inequality) OR (learning inequality)) ))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( wage and garding inequality ) or ( wage and ((warning inequality) OR (learning inequality)) ))*".