Perhaps you should try some spelling variations:
2.3 institutions » 2.3 institutional, 13 institutions, 3.3 institution
c institutions » c institution, 8 institutions, 7 institutions
5 institutions » 5 institutional, 5 institutionen, 5 institutionelle
2c etc » 29 etc, qc etc

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: %22associations%((((2((c institutions) OR (5 institutions))) OR (2.3 institutions))) OR (((c institutions) OR (5 institutions))))%2c etc %_ bolivia%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22associations%((((2((c institutions) OR (5 institutions))) or (2.3 institutions))) or (((c institutions) OR (5 institutions))))%2c etc %_ bolivia%22".
• Adding a wildcard symbol may retrieve word variants: %22associations%((((2((c institutions) OR (5 institutions))) or (2.3 institutions))) or (((c institutions) OR (5 institutions))))%2c etc %_ bolivia%22*.