Currently, this is how a full search system looks like.
This is rather ugly, at least not sexy at all.
It's based on clumsy ideas such as that free query parser that tries to guess which Boolean operators link each keyword together.
But why trying to guess? Because the searcher doesn't input explicitly any operators inside the query. The user's information input interface provided by the search bar is too narrow.
The fact of the matter is that current search interfaces are still basic search bars and therefore don't get you excited about using "AND", "OR" or "NOT".
"Web search engines such as Google have popularized the notion that a set of terms typed into the query box carries the semantic of a conjunctive query that only retrieves documents containing all or most query terms".
This is a quotation from "Introduction to information retrieval", written by Christopher Manning , the associate professor at Stanford that helped Larry and Sergey do some cool stuff in 1997...
Again, let's stop trying to guess systematically for the user, for a minute. Let's enable searchers to put more information. Let's try to process that additional information in an elegant and efficient fashion. And let's try to create some substantial data that will be used to create algorithms that will be the basis for systems whose purpose will be to guess for the user.
I think that technological innovation is based on a very tight collaboration between "humans" and "machines", a "human" being an electrochemical computer, a "machine" being an electronic computer. I think that technological innovation is based on an alternation between humans' brains contribution and machines contribution, all the time.
And search is no exception.