| Clue | Source | Date |
|---|---|---|
| Be thoughtless not to know at all (4,2,4) | ||
| Are empty-headed? I don't know (4,2,4) | ||
| Be quite useless, but be totally unaware of the fact (4,2,4) | ||
| Be totally stumped | LA Times Daily | 21 Aug 2021 |
| Be totally stumped | The Washington Post | 21 Aug 2021 |
| Can't imagine | LA Times Daily | 19 Mar 2016 |
| Be totally clueless | Newsday | 27 Jul 2015 |
| Be totally clueless | ||
| Be completely clueless |