How to reproduce it :

• Use the demo repository,
• Create a new workspace : delta-project
• Declare the demo admin  user as manager of this workspace.
• Give to the admin user all rights on workspaces elements
• In this workspace, add a pdf document with the word "book" inside
• In the demo site, add a search engine service into a page
• The parameter of the service should have the checkbox "Extend to the workspaces" active
• In the parameters of the service I also active the multisite checkbox
• Preview the search page of the demo site
• launch a research with the word "Book"
• The PDF that I added in the delta project does not appears in the results

If I launch a research without keyword, the document of the wiki appears in the search results