Perhaps you should try some spelling variations:
22income distribution » income redistribution, genome distribution, income distributional
income distributions » income redistribution, time distributions, discrete distributions
70 developing » 10 developing, 20 developing, 30 developing

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: %((((22income distribution) OR (income distributions))) OR (income distribution)) %70 developing countries%22.
• Adding a wildcard symbol may retrieve word variants: %((((22income distribution) or (income distributions))) or (income distribution)) %70 developing countries%22*.