Where are you search from?If you are using Edit -> Find (Ctrl+F) use "Exact".If you are using the search box in the upper left of the register that will search all fields that contain any of the text you put in. It is a "generic search" it isn't doing something different in each field like only giving you that amount.
It should be a simple task/execution and it should only include the account that is at hand.
Very good question. I have been wondering about this for a while. How I get around it is to search for the amount, and then sort the results /register by amount. At least then, you can focus down to what you are you looking for.