Perhaps you should try some spelling variations:
learning inequality » learning quality, measuring inequality, deepening inequality
garding inequality » garding's inequality, hardy inequality, hardy's inequality
hardy inequalities » valid inequalities
rising inequality » reducing inequality, increasing inequality, addressing 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 ((learning inequality) OR (((((((garding inequality) OR (rising inequality))) OR (hardy inequalities))) OR (earnings inequality)))).
• Adding a wildcard symbol may retrieve word variants: wage and ((learning inequality) or (((((((garding inequality) or (rising inequality))) or (hardy inequalities))) or (earnings inequality))))*.