Then you are probably using it wrong.
You should make sure you are on the main forum page, not in a topic or a specific area, otherwise it will only search that specific board or topic.
This topic may help, that's what popped up in my search with "engine room herkules atlas" as input.
http://www.shipsim.com/ShipSimForum/index.php/topic,7246.0.html
Regards,
Fred