comparing documents in 2 indexes

[Elshaimaa Ali <el...@hotmail.com>]

Hi all
I have a problem that might be very trivial but I don't know how can I solve it using Lucene
I created an index with Lucene for a huge data set around 3 million documents in various domains and another index for a corpus of 30 documents in a specific domain.for every document in the small corpus I want to find  a similar document from the huge one. does anyone knows if the Lucene searcher can do that.
secondly: how can I view the terms of a document and their frequencies form the generated index.
thanksshaimaa