cs 2.0.4 meta fly for filtering result

hi, my title is explicite but,

in cs-cart 2.0.x have a really good seo for the filters , when you filterring product by atribut automaticly the word or words are placed in the tilte of the page.perfect for long tail…

to offering unique result for google I search the tips to allows unique fly metadescription for filtering page

per ex:


shoes : 50$ to 100$ : sport: nike: blue


(cat name) + need shoes 50$ to 100$ : sport: nike: blue ( site metadescription default)

for the moment cs-cart allow for filtering page the default site metadescription

anyone knows whats files to modify tis funcion?