[Woocommerce] How to get manual Title and Description of Product

Hi,
I would like to check if, for the current product, there is a costum Title or Description value.
If there isn’t, I use the funciotn add_filter(‘wpseo_title’,’change_yoast_page_title’) to write the default Title and Description.

I tried to use the function get_option(‘wpseo_titles’) but doesn’t return the value of custum Title.

Thanks a lot