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

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 ((warning inequality) OR (((learning inequality) OR (garding's inequality)))).
• Adding a wildcard symbol may retrieve word variants: wage and ((warning inequality) or (((learning inequality) or (garding's inequality))))*.