How shall I do to move Fragment folder from CS4 to CS6
Do you mean the Snippets folder? If so, it's located in your personal configuration folder. The location depends on your operating system. See the following FAQ for details: http://forums.adobe.com/thread/494812.
Just copy the folder from the CS4 location to the equivalent CS6 location.
For example, my Snippets folder in CS4 is here on Windows 7:
C:\Users\David\AppData\Roaming\Adobe\Dreamweaver CS4\en_US\Configuration\Snippets
The CS6 folder is here:
C:\Users\David\AppData\Roaming\Adobe\Dreamweaver CS6\en_US\Configuration\Snippets
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