How to work with AD Groups and Qlik Dashboard

I am not sure what you mean by "The problem is the integration only allow me one AD Group in Qlik connector.". Can you clarify this part?

In general you need to ensure that your users have the attributes that you want to utilize. In your case the attribute is the group membership. Setup User Directory Connector (UDC) to sync attributes to your accessing users, and remember to setup a sync task to keep the attributes up to date.

User directory connectors ‒ Qlik Sense

After successful sync validate the attributes in Users list in QMC, by clicking the next to userid.

Users ‒ Qlik Sense

With attributes properly setup you can start utilizing them in your security rules.

AD groups come through nicely using the UDC creating a stream for group a and a stream for group b and setting security rules to manage access should be straight forward.