How do I re-size the pop window that displays products to insert into invoice?

How do I re-size the pop window that displays products to insert into invoice?

Hi.
How do I re-size the pop window that displays my products & servies to insert into the invoice?
As you can see in th eimage below, currently its too narrow and I cannot see the "go" button and have to keep using the "enter" button on my keyboard to submit a search for an item.





Cheers,
Danny.