Steps to reproduce:

1. Prepare a test eZ Studio installation, clean;
2. Install Solr Bundle (https://doc.ez.no/display/DEVELOPER/Solr+Bundle), make sure Solr service is running;
3. In the admin interface, create a new Content Type with one searchable and mandatory attribute of type "ezkeyword":

Name: 5899
Identifier: 5899

Attribute type: ezstring

• Name: Title
• Identifier: title
• Is required: checked

Attribute type: ezkeyword

• Name: Title
• Identifier: title
• Is required: checked
• Searchable: checked

4. In the "Content structure" section, create a new content based on the new Content Type, with suitable test data;
5. Search for terms inserted on the "ezkeyword" field on the new content. No results will be returned;
6. Also, go to Solr's own admin interface, and search for those terms on the "Query" and "Schema Browser" sections. No entries will be found.