Use Tags and Smart Folders in Notes on your iPhone and iPad - Apple Support

Use tags to quickly categorize your notes so you can easily find them later. Just add one or more tags — like #work or #shopping — anywhere in any note. You can also use tags together with existing folders to search and filter your notes across multiple folders.

Organize your reminders with tags on iPhone - Apple Support (TM)

A Closer Look at Apple Notes's Smart Folders – The Sweet Setup

Search for email in Mail on iPad - Apple Support

Organize your notes in folders on iPhone - Apple Support

How To Create Smart Folders and Tags in the Notes App

How To Quickly Organize iPhone Notes Using Tags & Smart Folders

How to use Smart Folders in Notes app on iPhone, iPad, Mac

Annotate books in the Books app on iPad - Apple Support

How to Use Note Tags and Quick Notes - TidBITS

How to use Smart Folders in Notes app on iPhone, iPad, Mac

What Are Smart Folders In Notes App And How To Use Them - iOS Hacker

Use Notes on your iPhone, iPad, and iPod touch - Apple Support

Draw or write in Notes on iPad - Apple Support