Error retrieving http://vnexpress.net/rss/gl/xa-hoi.rss

Not sure why that feed is not working - looks like the server cannot retrieve it. Strangely, putting a single item through works fine, e.g. http://vnexpress.net/GL/Xa-hoi/2011/01/3BA25124/

Not sure I understand your new line question.

Finally, the code can process any number of feeds, so you don't need to install multiple times.

Oh the newline question means if an article has 3 paragraphs, when I run your program it is combined into 1 paragraph.
Another question, how far back does your script go? Can user read articles from last week or last month if he keeps clicking next?
How do I set that up?
Thanks

Full-Text RSS tries its best to fix badly marked up paragraphs but it doesn't always succeed. If you've got an example URL where this happens I can take a look.

The script can only go as far back as the feed you supply it. The original feed is essentially a list of URLs. That list can span 1 hour, 1 day, 1 month or many years. We only work with the URLs in the original feed. So, for example, If the original feed only contains items from today, that's all we can extract from it.

Hope that clears things up.

Interestingly, when I click refresh, sometimes I m able to get the feed from http://vnexpress.net/rss/gl/xa-hoi.rss.
But sometimes it returns an error.
Google Reader however works ALL the time

They probably have server issues if you're not able to load it directly in your browser. If Google Reader works it's because they cache the results and don't depend on the feed being accessible the moment you add it - they poll it periodically and pull in new content, so if the server is down periodically, it doesn't show.