I have blank results in search on my iPhone

I would try to restore your device to factory settings.

To perform that procedure, create a full backup of your iPhone, then follow the steps provided in this support guide, and, in the end, set it up as new:

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

When done, test your device for some hours without restoring data from your backup. If it works fine, restore data form your previously made backup:

Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Please, let me know how it goes.

Giulio

Perhaps what you are searching for does not exist on your phone.

Perhaps you had a bad connection yesterday (maybe due also to a temporary Apple Servers problem).

Keep on testing your device.

Regards

Giulio

Glad it helped :-)

Giulio