@yuhuihuang. Thanks for posting the link. The problem is that Mootools is not being loaded on that page of your site. Something is blocking it from being loaded. If I go the home page, Mootools is loaded. However, when I go to the page with the listing, it is not referenced at all. You can verify this your self by looking at the source html on both pages, and you will see mootools-core.js and mootools-more.js as a script reference on the home page, but not on the listing page. These files should be loaded on every Joomla page, not just the home page.
Yes, files can be viewed in a new tab or window. However, the normal preview will work once you get Mootools to load like it should.