When search engines look at your site they look at the page titles, Meta Desc and Meta keywords to see how to catagorize your pages. They want there to be meaningfull data as page titles and they want all of your pages to have a page title as well as a desc and keywords.

To assign these elements to your virtual pages you need to edit your virtual pages and click on the meta data tab. There you will find the fields that need to be filled out for your site to have meaningfull meta data. keep your page titles to a brief description 50-60 characters.
meta desc should be no more that 200 characters and keywords should also be no more than 200 characters.