Search api & solr search => no results found
There is a 'solr-devel' module to help http://drupal.org/project/solr_devel. 

Make sure that the query works directly in the solr native search page. Isolate the drupal side this way. 

Make sure that you have updated schema.xml and solrconfig.xml with the ones that come with the module as per the module README.txt. Reindex.


  Move apache-solr-1.4.1/example/solr/conf/schema.xml and rename it to
  something like schema.bak. Then move the solr-conf/solr-1.4/schema.xml
  that comes with this Drupal module to take its place. 
  
  Similarly, move apache-solr-1.4.1/example/solr/conf/solrconfig.xml and
  rename it like solrconfig.bak. Then move the
  solr-conf/solr-1.4/solrconfig.xml that comes with this module to take
  its place.