Perhaps you should try some spelling variations:
income redistribution » income distribution, income distributions
time distributions » time distribution, size distributions, stable distributions
gene distribution » one distribution, zone distribution, general distribution
7.2 developing » 5.2 developing, 3.2 developing, 12 developing
72 developing » 762 developing, 12 developing, 22 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 redistribution) OR (gene distribution))) OR (time distributions)) %((72 developing) OR (7.2 developing)) countries%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((((income redistribution) or (gene distribution))) or (time distributions)) %((72 developing) OR (7.2 developing)) countries%22".
• Adding a wildcard symbol may retrieve word variants: %((((income redistribution) or (gene distribution))) or (time distributions)) %((72 developing) OR (7.2 developing)) countries%22*.