Why the wdphotos apk does not work?

have you one know why the wdphotos can not search my cloud? display nothing .
there are 100000’s photos in my cloud.but I can’t see that on the wdphotos.

Are you on a Windows PC or an Apple etc? See example image below from my Windows 10 Home Desktop computer. It depends on where your pictures are located on your My Cloud and how you want to search for them. Click on, tap or activate image to enlarge it.

You’ll see that I have Network>WDMCLOUD>Horace>Pictures open and at the end of that bar it says Search Pictures.

“wdphotos apk”? Uh where did you get that APK? WD Photos I believe had been End of Life for a while now. The only currently supported Android app for the My Cloud is My Cloud for Android which can be found in the Play Store.

Currently the only official WD supported methods of remote access to a My Cloud is MyCloud.com, the WD My Cloud app for iOS and Android, or the insecure FTP access option.

Edit to add: The official WD notice of retiring of the WD Photos Android app.

Software Notice - WD Photos Being Retired 5/9/2017
https://community.wd.com/t/software-notice-wd-photos-being-retired-5-9-2017/185596

You can reinstall it from the Google Play Store for the latest version.