[edited:] Apparently you can retrieve comments, and Mudassir's link should get you there if you want to go that way, though. Glad I supplied an alternative method for you, though, if it does what you want!
If you're looking for another way to "store" extra information, there are many other ways of doing it. You could use data-* attributes, or even recycle an existing attribute such as title or ID. Then you would have:
<td colspan="3" title="呜呜呜旺旺旺旺王旺旺旺旺wwwwww">呜呜呜旺...</td>
..and the way to retrieve it with jQuery would be something like:
$('td:eq(3)').attr('title');
(The td:eq(3) is probably not the most flexible selector you could be using; I just grabbed one that worked. If we know the basis for selection, we can provide something more flexible)