Weekly sales report for individual Items

We would like to pull a weekly sales report on individual products for the last 6 months. What we would like to see is the total sales per week per individual product / retail item (not the total only which is what we seem to be limited to). Please can you direct us to a resource that shows us how to do this.

An example: We would like to see how many Hummus 200g is sold per week over the last 6 months i.e. approx. 24 weeks of sales reports on an individual item.