Location responsive filter widget

Dear forum members,

Im looking for a widget that basically works like the existing “taxonomy search” widget, but is able to search taxonomies only in the current category.

Though the taxonomy based search works really fine, customers at the moment only receive global search results – e.g. they navigate to “Shop > categories > electronics > rc helicopters” and now use the widget located in the sidebar, to filter out all “black” ones, they will get displayed every shop article (toasters, drilling machines .. so on) related to the tax “black”.

I hope my description is easy to understand. If there is already such a function or I’m doing a major mistake / doing something generally wrong – feel free to correct or criticize me.

Thank you for your help.