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