Okay, let's do this one more time:
Say you searched for 250 x 190 x 80
And say these are your choices:
250 1 1
250 500 1
250 1 500
250 190 1
250 190 500
240 180 70
*CLEARLY* the first 3 choices are useless. Yet each has a perfect match on length.
Equally clearly the next 2 choices are useless, even though each has a perfect match on both length an height.
So the only reasonable choice is the last one, even though none of its dimensions is a perfect match.
You see my point? THERE IS NO POINT in looking for a perfect match as a separate operation. What you really want is, as I suggested, the CLOSEST match on all 3 dimensions. But, again, you have to tell us what CLOSEST then means.
Is it the sum of the differences being closest to zero? The product of the differences being closest to zero? What?
An optimist sees the glass as half full.
A pessimist sees the glass as half empty.
A realist drinks it no matter how much there is.