The individual search boxes at the top of the window can be used to narrow down your search for the target customer, that is, the customer that will remain. Also use column sorting capability of the grid to sort by any column. Although not as fast or useful, you can also use vertical scroll bars to scroll through the list.
Highlight the selected target customer. Remember that you are merging the first customer you selected INTO the target customer. After merging, the first customer selected will no longer exist.
