Perhaps you should try some spelling variations:
22income distribution » income distribution, income redistribution, genome distribution
monomer distribution » money distribution, genome distribution, isomer distribution
income distributions » income distribution, income redistribution, time distributions
72 developing » 7.2 developing, 762 developing, 2 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 (monomer distribution))) OR (income distributions)) %72 developing countries%22.
• Adding a wildcard symbol may retrieve word variants: %((((22income distribution) or (monomer distribution))) or (income distributions)) %72 developing countries%22*.