required form fields not populating

I have a PPC campaign that targets customers in asia.  When they click on the ad, it lands on a Marketo form landing page.  However, when I get the form fill alerts, the forms come out blank, 3 of them have come from China.  Do I need to change the charset for the required fields? If so which one?  

On another note, does any one have any recommendations for doing international ppc campaigns and landing pages.  There's 2 geographic areas we're targeting asia (Japan, Hong Kong, Malaysia, Singapore, China and India) and Europe.