From what I can understand by reading your description, this is something that you will need to implement in the indexing mechanism of your search engine -- when the user provides the engine with a search phrase, the backend needs to already know the difference between "an article on Dr. King" and "an article about Martin Luther and his dealings with german royalty".
So, without being able to get into much detail, I think you need to implement this in your backend database. Maybe you should add a column that indicates the state of a certain URL -- is it an article on Dr. King or a about his dealings with german royalty? Of course, the hardest part of such a project would be to implement logic into the indexing mechanism that calculates that value of this column. Maybe it needs to be done manually?
If you find a working solution, Giff, please feel free to post it here. I'm sure that would be interesting reading for many of us. Good luck!