Find all numbers in a integer list that add up to a number

I was asked this question on an interview. Given the following list:

[1,2,5,7,3,10,13]

Find the numbers that add up to 5.

My solution was the following:

#sort the list:
l.sort()
result = ()
for i in range(len(l)):
    for j in range(i, len(l)):
         if l[i] + l[j] > 5:
             break
         elif l[i] + l[j] == 5:
             result += (l[i], l[j])

The idea I presented was to sort the list, then loop and see if the sum is greater than 5. If so, then I can stop the loop. I got the sense the interviewer was dissatisfied with this answer. Can someone suggest a better one for my future reference?

via Chebli Mohamed