RAW, I'm 99.9% certain this combo doesn't actually interact at all, but given that GMs can vary in leeway on RAI and/or house ruling minor details, I wanted to get a feel how the members of this board would feel:
Would you, as a GM, allow the feat
Hawkeye to increase the range on the effect of the spell
Cloud of Knives?
If context is needed to make a decision, the particular character is built ranged, thrown, and would have the spell as a magic item.