Need suggestions for Google Base PLEASE

Hello,

We are using Google Base ‘improved ‘ plug-in to our open cart (version - 1.4.9.3).

We would like to enhance and optimize the number and percentage of products that are being picked up by Google base. Our feeling is that currently the number of products showing in Google Base versus the number of products in our catalog reflects an under-optimization of this plug-in’s functionality and potential, which we would like to maximize.

Do you have any suggestions for Google Base application or Merchant center settings ?

Expecting help from Open cart community/experts .

Thank you.