Don't strain at a gnat when the big problem is obvious.
strain at a gnat
idiomto make a mountain out of a molehill
Origin
disputed originFrom the King James Version of the Bible, verse Matthew 23:24.
You focus on tiny typos in the report while ignoring the fact that the data is completely wrong; you really strain at a gnat.
It is frustrating to watch the committee strain at a gnat regarding minor formatting rules while the entire project budget remains dangerously unapproved.