run short of (something)
To near the end of a supply of something. We're running short of paper towels right now, so use them judiciously.
run short (of something)
to begin to run out of something. We are running short of eggs. I always keep enough so I will never run short.
run short
Use something up so that a supply runs out or becomes insufficient, as in We ran short of envelopes, or The organization is running short of money. [Mid-1700s]