how to use 2 different database in one wordpress?

Please see the linke http://www.designexpanse.com , this is a main wordpress now I am going to install another wordpress within the same domain under another folder. The theme will be same but I want to use the main wp database with another new wordpress under different folder. Like I want to use the “Random Designs” section showing on the left bar, “Most Viewed Design”, “Most Rated Design”, “Highest Rated Design” which is currently showing on the footer. I need the same sections listed above on the new wordpress which installed under different folder. I hope you all can understand this.

Please help and advice me to do this so I can start article section for this website after setting up a new wordpress.

Thanks you in advance