manual keyword inheritance

[jzhao]

I have a folder like this:
budget - 2005 - some files
- 2006 - some files
- 2007 -- some files

the first level budget have "budget" as keyword, the second level folder 2005 has "2005" as key word. I would like all 3rd level files have "budget" "2005" keywords inherited so why I search, I put "budget 2005" , all those files are listed.

This seems to be a natural manual keywords inheritance. This is a very useful funtion I am deperately looking for.

Thanks

Jzhao