[Closed] Microsoft CRM 2011 help needed: Views

I need to create a dynamic view, normally this is ok but i am having a nightmare and rapidly coming to the conclusion this what i am trying to do is impossible

I have to look at the accounts table linked to the sales order table and select all customers who have bought a specific product. But i only want those customers who have not bought it for the last three months.

I can get a list of all customers who have bought, i can get a list of those who have bought recently, but i can see no way of getting only those customers who have not bought recently.

I can do this easily in SSRS but it has to be a view, reps being reps i have to make this as easy as possible for them. Particularly on a newish install and a number of the reps believing that CRM is big brother so looking for any excuse not to use.

I am wondering if it is possible to edit the Fetch XML behind the view, whether i can use a web resource, workflows, anything really.