Mail search messed up since upgrading to MacOS 27

It is completely understandable to feel frustrated when a system upgrade breaks a precise workflow you have relied on for decades. With macOS 27, Apple completely revamped the core architecture of its Spotlight and Mail search engines. They shifted away from localized keyword caching toward a semantic, intent-based search model. While this was intended to help users find things without exact phrasing, it completely disrupted the rigid AND filtering logic required for managing vast archives. 

Since the system now defaults to "smart" fuzzy matching and typing AND no longer functions as a traditional boolean operator, you can force the precise filtering you need using these technical workarounds:

1. Force Strict Keyword Filtering with Quotes

Instead of letting the semantic engine guess your intent, wrap each mandatory keyword in double quotation marks

• Instead of: project update delayed (which treats it as a phrase or semantic concept)
• Use: "project" "update" "delayed"
• This signals to the underlying engine that the specific, exact string must be present, effectively restoring the strict AND constraint.

This is a helpful reply in that it explains what's going on in Mail search in [insert Apple device here]OS 27, but it's nauseating, in that it (1) explains why Apple made search in Mail worse for (I'm guessing) at least 50% of users and use case, and (2) there is, evidently, no way to revert the behavior to the previous, actual-useful-in-the-real-world behavior.

Note that the nausea is not an intentional effect of the poster, but a natural reaction to Apple's headlong plunge into AI for the sake of AI and not at least giving users a choice. (Note that this behavior occurs even when Siri is turned off.)