Perhaps you should try some spelling variations:
income distributions » income redistribution, time distributions, size distributions
turf developing » stuff developing, future developing, tariff developing
2f developing » f developing, 7 developing, self 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 distributions) OR (income distribution))) OR (discrete distributions)) %((2f developing) OR (turf developing)) countries%22.
• Adding a wildcard symbol may retrieve word variants: %((((income distributions) or (income distribution))) or (discrete distributions)) %((2f developing) or (turf developing)) countries%22*.