Land Guo

Hi, All  Master SEOERS,

I have a  site  http://www.dfdsolar.com , there were 76pages  crawled
by googlebot, and 25pages by Yahoo,1page by MSN , and  the site can be
stand on the first page  on google  if  put keywords "newest solar
product","newest solar products" "newest solar toy" .For  now , i want
to change another keyword. Is it effect  the old ranks ?

Thanks
Regards

Land