XF 1.5 how can i add like (data-description) part,in another places in the forums?

If you're wanting to integrate another library, you'll be looking at at least making template changes where necessary to add what you want. In terms of using XF, you can use the Tooltip class and a title attribute. I wouldn't use the description tooltips as an example as they're different, but most other "simple" tooltips will show you roughly how to do it.
 
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