Every nook and cranny
Definition 1 of 1
Pro Tip 1/3Complete Thoroughness
Emphasizes a very detailed and thorough search or inspection. 
The detective checked every nook and cranny for clues.
Pro Tip 2/3Hidden Areas
Refers to parts of a place often ignored or overlooked. 
He cleaned every nook and cranny, including the space behind the fridge.
Pro Tip 3/3Metaphoric Use
Can be used metaphorically to mean all aspects or parts of something. 
Every nook and cranny of the program was tested for bugs.