Yesterday I attended a seminar talk titled "Cluster presentation of reflexion groups", and before it I tried to ask Google what is a "cluster presentation" --- but all one can find on this request is about databases or social studies.

Another example: try to find something on "geometrical groups" and not "geometric group theory".

I think this is a very common problem, when you are interested in some area you don't know anything about and trying to find some texts on it --- but it's very hard if you don't know what exactly to look for. Of course if you have someone to ask, it's not a problem anymore, but usually you don't.

So the question is: how to start learning an advanced topic if you don't have any texts or guidelines about it (and have nobody to ask except for MO community)?