You can search for a recently opened spreadsheet within Numbers, or use Spotlight to search for a spreadsheet by title or by its content. Spotlight searches your Mac and email attachments.
Do one of the following:
Find a recently opened file: In Numbers, choose File > Open Recent (from the File menu at the top of your screen), then choose the spreadsheet. Numbers shows the last ten spreadsheets you opened.
Search for a file by its title or content: Click the Spotlight icon (it looks like a magnifying glass) in the menu bar in the top-right corner of your screen, then enter one or more words from the spreadsheet title or content. In the search results, click the spreadsheet to see a preview of it.
To see the path to where the spreadsheet is located on your computer, click the spreadsheet, then press the Command key. To open the spreadsheet, double-click it.