Querying the assets in Centrasite

Hi,
I have created few customized assets in centrasite and tried to query it .
For example i have added a asset called Component(Customized not predefined by centrasite) and also defined properties for it like the Owner of the component, description and so on, added a attribute of type relationship as a property, example the component implements package( assosiation relationship attribute)
When I tried to query these attributes uisng advanced query

  1. the query which has a owner name=xxxx returns results also
  2. the query which implemetns package ABC returns result.

But the the combination of these queries with the AND operation fails , throws exceptopn though there are results matching for it.

Can anyone say why this happens

Is it possible to query a asset with ,more than one customized attribute?