OK, i think is the memory problem cause the slider occur this happen.
More than that, my website suddenly cannot access. I found the problem is caused by the following plugins:
Essential-Grid, Mega_main_menu, shortcodes-ultimate
After disable them, the website will able to run.
What wrong with these plugins? How can i fix this issue?
How can i fill up the theme in this topic?
The theme i use is http://demo.roadthemes.com/organica/
Thank you =)