Perhaps you should try some spelling variations:
22income distribution » income distribution, income distributions, income redistribution
monomer distribution » money distribution, genome distribution, isomer distribution
time distributions » time distribution, size distributions, stable distributions
2 developing » 2 development

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 (time distributions)) %2 developing countries%22.
• Adding a wildcard symbol may retrieve word variants: %((((22income distribution) or (monomer distribution))) or (time distributions)) %2 developing countries%22*.