So... I am using a digital voice recorder to record anything I see important, ranging from business to private, from rants to new business ideas.

Every finalized idea is one wma-file. I wrote a program to sort the wma-files into folders. From time to time I listen to the wma-files, convert them to text(manually) and insert them into a mindmap with mindmanager, which I sort hierarchically by area and type in turn.

This works very well, no idea is being lost, when I am out of ideas for a special topic, I listen to what I said and can get started again.

What could a search system look like that finds links between thoughts(written in the mindmap and in the wma files) or in general gives me good search results even when the keyword I searched for is not present but a synonym of it or related topic(for instance flower should output entries containing orchid aswell, even if they contain orchid but not the very keyword flower).

I prefer something ready-made but small adjustments to a given system are fine aswell.

How would you approach this task?