...
We can do it by pixel events and then using it in an audience or just creating an audience. This example will show the first way:
We're looking for users interested in organic shampoos or shower gel who get to our shop from Google
1.Create an event - Source Google
...
2. Create an event – organic shampoo. shower gel 
...
If we select Capture User Attributes, we can collect exact product names and show products in the ad, email, etc. https://wiki.mapp.tools/display/DMPCustomers/Capture+User+Attributes 
...
3. Create an audience that is any of those two pixels and set the expiration time. Like the abandoned cart case, we can remove the user who already bought a product from this audience.
...