Nemopuk and multiple users on a system

Hi all,
I have two users on my laptop, both are for me mean i am the owner. Previously i activated Nepomuk and it took around 2GB of space for indexing in home directory. Later i have problems with the current user settings and created new one and setup it up. Just yesterday i was searching for a file, nemopuk search return 0 results which was indication of that it is not enabled for the current user. I enabled it and it start indexing the files/dir i mentioned in the configuration. Until here its fine.

Now my question is why it index the files/dir again and took around 2GB space, suppose it should be indexed once and every user can search if they are allowed to access the files/dir. On some systems there are many users, is it a good idea to index the files/dir for each user and took 2GB space.

One more thing, i tried to search some folders and also played with the settings but it just return files. Is there any setting to enable it to search for folders also?

Any feedback will be appreciated.