Possible Clues:

• Hairdressing tool (used for for careful examination?)
• Thorough-search metaphor
• It may help to scrutinise charge by canine groomer
• Metaphor for a thorough search
• Investigators should go through with it
• Symbol of investigative thoroughness
• Symbolic instrument for a thorough investigation
• One used to search thoroughly and elaborately cold bit of the moon
• Hairdressing implement with close prongs (for careful examination?)