1.
nitpicking; catching someone on slips; fault-finding
the act of finding fault with trivial mistakes in what someone says or does, often ignoring the main point
揚げ足取りはやめてください。
Please stop nitpicking.
Etymology
From sumo wrestling terminology: 揚げ足 refers to lifting an opponent's leg to trip them. 揚げ足取り means exploiting an opponent's momentary vulnerability.
Usage
Strongly negative connotation. Implies pettiness and missing the larger point in favor of trivial criticisms.