Explanation:

- The phrase “to split hairs” means arguing about very small differences or unimportant details.

- Option 1: To sidetrack the issue – This means to avoid the main topic. Not the same as splitting hairs.

- Option 2: To quarrel over trifles – Arguing over trivial things. Very close, since “splitting hairs” is about small details.

- Option 3: To indulge in over-refined arguments – This best matches the meaning. It refers to getting lost in detailed, subtle arguments.

- Option 4: To find faults with others – This is about criticism, not fine distinctions.