Loop thru every combination

Also posted here:
http://www.ozgrid.com/forum/showthread.php?t=201337

Hi,
in attached file I made example of a Range method to find by country a combination of 2 values that add up to amount on the right.
However, Belgium doesn't get its Cell Addresses, because 138 is Sum of 3 values (E9, E10, E16).

I look for a looping mechanism, that would go through each 2-combination of values until it finds the result,
otherwise would continue with 3-combination, 4 .. up to all items combination necessary to find respective SUM.

Example:
A-B, A-C, A-D ..... A-Z
A-B-C, A-B-D ...A-B-Z ; A-C-D .. A-C-Z ...

Thank you Arkadi