Perhaps you should try some spelling variations:
widening inequality » deepening inequality, reducing inequality, rising inequality
learning inequality » learning quality, garding inequality, deepening inequality
hardy's inequality » hardy inequality, holder's inequality, harnack inequality
wage » wave
earnings » warning

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 ((widening inequality) OR (((((((learning inequality) OR (((measuring inequality) OR (measuring quality))))) OR (hardy's inequality))) OR (earnings inequality)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "wage and ((widening inequality) or (((((((learning inequality) or (((measuring inequality) OR (measuring quality))))) or (hardy's inequality))) or (earnings inequality))))".
• Adding a wildcard symbol may retrieve word variants: wage and ((widening inequality) or (((((((learning inequality) or (((measuring inequality) OR (measuring quality))))) or (hardy's inequality))) or (earnings inequality))))*.