Press Ctrl+K (Cmd+K on a Mac) and type. Search looks through page titles and text, and also finds boards, forms and sheets by name.

Open search
Press Ctrl+K (or Cmd+K) anywhere in the workspace, or
choose Search in the left rail.
Search
Type a few words. A page must contain every word, in its title or in its text, and partial words work, so leav finds leave.
Results are ranked so the best match comes first:
A page whose title is your whole phrase comes first.
Matches in a title count for more than matches in the text.
Pages you changed recently, and pages you open often, rank a little higher.
Each result shows its title, where it sits, and a short passage with your words highlighted.
What it finds
Pages, including their sub-pages, with the collection or parent shown beside the title.
Board cards, labelled with the board they belong to.
Boards, forms and sheets, by their name.
You only see what you have access to. A private page that is not shared with you never appears.
Open a result
Use the ↑ and ↓ keys to move through the list and press Enter to open one, or click it. The page opens, and the Pages panel opens the collections above it and highlights it, so you can see where it lives. Press Esc to close search without opening anything.
Good to know
Pages in the 🗃️ Archive and trash and the trash are left out of results.
Search does not look inside form responses or the rows of a sheet.
Tip: search for a person's name to find the pages where they were mentioned.