Network Search not returning results

Hi, I tried looking for a forum post on this but can't seem to get it to work. I have a multisite installed on the domain indicated. I have three fo your plugins that apply to this query: CustomPress, Global Site Search and Post Indexer. I have activated all relevant plugins such as the indexer, however, when I use the search on the new site search page, I type the title of a custom post type (a vehicle in this case) 'Mercedes'. It returns no results. I've tried broader terms and always seem to get no result. Please help