nitpicker       
noun [ C ]  informal disapproving uk/ˈnɪt.pɪk.ər/ us/ˈnɪt.pɪk.ɚ/
 挑剔的人,爱吹毛求疵的人
someone who finds faults in details that are not important
  Some people may say I'm being a nitpicker. 有些人可能会说我是在吹毛求疵。 
 The nitpicker in me had to mention that the flat wasn't completely clean. 如果要挑毛病的话,那我必须得说这个公寓不是特别干净。 
 See: nitpick
 - More examples
 - He performed very well, but a nitpicker might think he wasn't exactly right for the part.
 - We get audited by some nitpicker who always finds something wrong.
 - She's a perfectionist, and a self-admitted nitpicker.