When searching the marketplace most threads that show up are from a few years ago and are no longer relevant. There is no way to limit the search to recently started threads - so that addition would be quite useful.
For exemple I want to search in forum "Buy, Sell or Trade > Sites" websites for sale in the last month with the keyword "health". I would use google to search for "site:forums.digitalpoint.com health" and set Search tools to "Past Month".
You may miss good sites on sale if the seller opts to not show the sale thread on search engines. So its rather best to do a search in DP itself.