Searching existing word returns none, but an empty search returns a list with all records ?

1. The reason I was getting zero results was because existing database records have the field search_index empty. I still don't know how to index old existing records.

   Page.objects.search("page", raw=True)
   []
   Page.objects.search("")
   [<Page: Page: Home page>, <Page: Page: About>, <Page: Page: Navigation>]