I'm working with 2 workbooks. WB1 is an order form that lists products and quantities (via manual data entry). I want WB2 to find all of the entries for one specific product (with multiple entries) on WB1 and populate the sum of the corresponding quantities on WB2.

For example:
Product Quantity
36ry38 100
32ry39 120
36ry38 50

I want WB2 to find all of the products "36ry38", sum the corresponding quantities (100+50), then produce the resulting value on WB2 (150).

What is the best way to go about performing this function?