Update:
After I turned off the Pagination, the problem was still there! Then I checked some articles and removed some strange text format which came along when we do copy-and-paste from other site, the layout appearance is ok.
So to conclude, can I assume that the broken layout problem is caused by the “strange format” in the articles?
If this is true then I can see the hard work ahead for us as we have just adopted this Teline IV template from the standard template of Joomla! I.e to clean all the unfriendly format in our articles (hundreds).
Any view?
Thanks