Synonyms for Faultfinding (same or very similar meaning)
WordNet sense 1 (persistent petty and unjustified criticism):
carping
WordNet sense 2 (depending on judgment):
judgmental
WordNet sense 3 (tending to find and call attention to faults):
captious
WordNet sense 4 (marked by a tendency to find and call attention to errors and flaws):
critical
From the ODE community, based on WordNet
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