Perhaps you should try some spelling variations:
income distributions » time distributions, discrete distributions, size distributions
genome distribution » genomic distribution, gene distribution, monomer 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: %((((income distribution) OR (genome distribution))) OR (((income distributions) OR (income redistribution)))) %72 developing countries%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((((income distribution) or (genome distribution))) or (((income distributions) OR (income redistribution)))) %72 developing countries%22".
• Adding a wildcard symbol may retrieve word variants: %((((income distribution) or (genome distribution))) or (((income distributions) OR (income redistribution)))) %72 developing countries%22*.