I've studied the link below: Storefront Source Code Getting Started.
According to the "Configuring content connection string" Section, I realized that the need to be placed physical address of "cms-content" of admin. but We've deployed web applications(admin and storefront) to dedicated server. So for a configuration with these conditions I read the link below: Deploy web applications to dedicated server
But this link is not yet clear how the "ContentConnectionString" was initialized.
ContentConnectionString storefront setting pointed to place where themes files stored and has default value ~/App_Data/cms-content.
VC platform, with installed module vc-content allows to manage themes files from manager UI and have similar setting CmsContentConnectionString.
If storefront and platform have installed on same Azure apps or dedicated server this both settings should pointed to same physical place and have follow valuesprovider=LocalStorage;rootPath=~\App_Data\cms-content in platform Web.config and provider=LocalStorage;rootPath={ vc-platform physical path}\App_Data\cms-content in storefront Web.config.
For case when VC platform and storefront have separated installation need to use azure blob storage provider=AzureBlobStorage;rootPath=cms-content;DefaultEndpointsProtocol=https;AccountName=yourAccountName;AccountKey=yourAccountKey to share themes files between storefront and platform.
We strongly recommend use store and change your theme in GitHub repository and use CI (continuous integrations tasks) for update themes on production and use admin UI theme management only for emergency fixes or other not historical changes.