His political ideas are from 'the Stone Age'. [=are from the distant past; are very out of date]
Their lawyer said that he would 'leave no stone unturned' in trying to find more evidence.
The researchers 'left no stone unturned' in their search for the original documents.
(..) ...remains one of our highest priorities. The theft of lab equipment from your school is also receiving our attention. Rest assured, no stone will go unturned... ...in our search for the person or persons responsible for this. If you have any questions, now would be the time. Sir. (..)2008 TvShow: Breaking Bad Title: A No-Rough-Stuff-Type Deal Season: 1 Episode 7