It is not possible to block specific keywords or searches with Qustodio.
On Google, Youtube and other search engines, however, Qustodio can enforce Safe Search, which forces Google, Bing and YouTube to filter all content flagged as inappropriate (also called “restricted mode”).
You can find this option accessing your child's dashboard > Rules > Web Filtering > Settings:
Read more about this feature here: How Qustodio monitors web searches
If you want to block a website or a category, follow these steps.