Yes, you can invoice as many jobs as you wish, whether they concern the same client or different clients.
When you're in your list of jobs, you simply have to select all the jobs you would like to invoice and click on the arrow > Invoice selected jobs.
The system will then open a window containing all the invoices you just created. You can click on the green icon on the right to open these invoices in a new tab. All these invoices will be added to your list of invoices.