Index XML File using Lucene.net in ASP.NET

I need someone that knows [login to view URL] to Index an XML file efficiently. Keyword here is efficiently. I can loop the document myself using an XMLReader but I need to know if combining the TERMS node is more efficient or not. I want to be able to search using any TERM or value in any Node and return the SERIAL NUMBER for that document. The XML file has many documents and each has the same structure, so each needs to be index separately. Each Block of Nodes starts with the SERIAL_NUMBER node and ends the <PHR> node. If you have used [login to view URL] please let me know.