Use metadata search. Data lists are modeled in alfresco in the same way everything else is. Each field is stored as metadata, so use metadata based search. You'll have to know what field exactly you're searching though. Look in alfresco-3.3c/tomcat/webapps/alfresco/WEB-INF/classes/alfresco/model/datalistModel.xml to try to figure that out.
As an example, if you were searching the dl:todoNotes property of a dl:todoList item, you'd type "todoNotes: @Action" in the search box.
I'm not sure if this text based metadata search capability is in 3.3, or if it was introduced in 3.3g though.