When you open the Google Photos app, you’ll see a list of your photos. Otherwise, you won’t be able to group by face.  Tap the ☰ menu and select “Settings.” Make sure the “Face Grouping” switch is in the On position. (You can turn this off at any time) Tap the back arrow to return to Photos. The search menu will expand, containing a row of several small face photos. If you don’t see any faces, this feature is unavailable in your country. Now you’ll see all the faces identified by Google in your photos. Don’t panic if you see two photos of the same person in this list—you’ll be able to group them later. A new screen will appear, with that person’s face at the top and the words “Who is this?” just beneath. ” A text box will appear, with a “New name” box as well as contacts from which to choose. Because labels are just to help you search your photos, nobody will see this name except you. The name will now be applied as that face’s label. If you saw more than one face icon for this person, group them all by assigning them the same label. You’ll see the face icons appear again. You’ll see the “Who’s This?” box at the top left corner of the screen again. The label and an icon of that person’s face will appear in the search results. A pop-up will appear, asking “Are these the same person?” Both faces (of the same person) will appear just beneath these words. ” Now both faces are assigned to the same label, meaning that when you type that label, photos Google associates with both face icons will appear in the search results. You may have to repeat this process several times for the same person.

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Write a summary of the previous text in Vietnamese:
Nhấn vào biểu tượng Google Photos. Bạn cần chắc chắn rằng tính năng Face Grouping đã được bật. Nhấn vào khung tìm kiếm. Nhấn vào mũi tên bên phải để xem tất cả khuôn mặt. Nhấn vào một khuôn mặt để gắn nhãn. Nhấn vào “Who is this? Nhập hoặc chọn tên. Nhấn vào dấu tích hoặc nút “Return” trên bàn phím. Nhấn vào khung tìm kiếm. Nhấn vào ảnh khác có người đó. Nhập nhãn mà bạn đã chọn trước đó vào. Nhấn vào nhãn trong kết quả tìm kiếm. Nhấn vào “Yes” (cùng một người).