some product pictures in list missing

[travv tree]

Hi,need someone's help

 

My product page cannot show every pictures of itself in the thumbs_list div until press the "Display all pictures".

But "Display all pictures" do not show in the first time loading to the product page.

It only display after choose one of the product colors.(When choosing a certain color, the list display correctly.)

 

I need my product page display all the pictures in thumbs list when viewers click into the page.

 

Thank you in advance.