Perhaps you should try some spelling variations:
22income distribution » income distributions, income redistribution, income distributional
genome distribution » genomic distribution, gene distribution, monomer distribution
self developing » relief developing, self development, level developing

Try widening your search to All Fields.

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 distribution)) %self developing countries%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((((22income distribution) OR (genome distribution))) or (income distribution)) %self developing countries%22".
• Adding a wildcard symbol may retrieve word variants: %((((22income distribution) OR (genome distribution))) or (income distribution)) %self developing countries%22*.