How do I search for files by words inside them instead of just their name?

You'll be able to: Find documents by text inside their contents using File Explorer search filters

The steps

1
Open File Explorer (WinE) and navigate to the folder or drive where you think your file is saved (such as Documents). The folder opens with a search bar in the top-right corner of the window.
How is this different from normal search?
Normal search prioritizes matching filenames, but Windows can also scan the actual text inside Word documents, PDFs, and text files.
2
Click inside the search box in the top-right corner (or press CtrlF or F3). The cursor starts blinking inside the search box, and a Search options tab appears in the top menu bar.
3
Type content:your_word (replace your_word with the actual phrase or number you remember) and press Enter. Windows filters your files and lists only documents that contain that exact phrase inside their pages.
Tip
If your search term contains multiple words with spaces, enclose them in quotes, like: content:"quarterly report".

It looks different on my screen

You can also click Search options in the top toolbar > File contents to turn on inside-file searching permanently for that folder.

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