@Pitt The new UI did not change anything regards to the search engine; the behavior was like this previously, too. @Nail1684’s response above has the right idea, but is inaccurate in the details.
To restrict your search to entries that contain both “demo” and “admin”, you must use an advanced search expression, with the following syntax:
>+demo +admin
The character > at the start of the search expression switches to advanced search mode, and prefixing a search term with the + character makes that search term mandatory. However, because advanced search mode only returns exact matches to your search terms (not substring matches), the above search expression will not find an entry named “demonstration administrator”. To include substring matches, you need to add a wildcard character at the start and/or end of the search term(s), as follows:
>+demo* +admin*
Also, please note that the advanced search functionality is only available in non-mobile apps.
Some users find the search function unintuitive, but this is how it has always worked. Three of the most active feature requests proposing changes to the search function are: