A short fuse: A quick temper. Jamie is known for his short fuse; just a few days ago he screamed at his coach for not letting him play.
Finding a needle in a haystack: Virtually impossible to find. Trying to get a new job these days is like trying to find a needle in a haystack.
38 more common idioms at:
https://www.thoughtco.com/common-english-idioms-3211646
