iOS problem parsing XML documents

If I use NSXMLParser parse following xml file

 
 
 123  
 234  
 

Then parsed in the 123 after b1 why stop parsed? If you want to resolve all of the nodes, and how?
Reply:
http://hi.baidu.com/richiechyi/item/9f6f832e2da3340842634af6
I can use this
Reply:

cited a floor reply:

http://hi.baidu.com/richiechyi/item/9f6f832e2da3340842634af6
I can use this

You use the tag attribute the way I tried, sometimes can sometimes skip this tag.
Reply:
Estimate your xml is not standardized, check there are no more spaces. There will be removed.