Perhaps you should try some spelling variations:
22income distribution » income distribution, income redistribution, income distributional
income distributions » income distribution, income redistribution, time distributions
genome distribution » genomic distribution, monomer distribution, income distribution
gene distribution » one distribution, zone distribution, general distribution
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 (((genome distribution) OR (gene distribution))))) OR (income distributions)) %72 developing countries%22*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((((22income distribution) or (((genome distribution) OR (gene distribution))))) or (income distributions)) %72 developing countries%22*".