About woocommerce, the cart in the header always shows 0

The situation is like this. I am using WP 4.2.2, php 5.5(ALSO I tried 5.4), apache 2.4 latest version of woocommerce.

My friend setup a website using WP and woocommerce. All work fine. But when I transfer it to amazon EC2, problem shows.

I can add products to the cart and it really exists in the cart, but the mini-cart in the header (The one shows the total value in the frontpage) is always 0 if it is the first time I add products to the cart. If I refresh the page, the mini-cart will shows the things I just added. And after the refresh, things start to work normally.

In a nutshell, if the mini-cart value is 0, no matter how many products I add, it is still 0. If there is and initial value there. Things will work normally.

I think the problem originates from the website transfer from Godaddy to Amazon. But all other functions are working properly. I also tried different kind of migration method like plugins, FTP, etc... But still cannot find a way out.

address: shop.wholeren.com The website is written in Chinese, if you want to test it, just drag to the bottom and click that [VIP SOMETHING 6 SOMETHING], and in the new page click add to cart. The mini-cart in the header locates at the top-right of the web.

Any suggestion?