Clarify where v-restore-user is searching for backup files

bin/v-restore-user

@@ -175,7 +175,7 @@ if [ ! -e "$BACKUP/$backup" ]; then
         downloaded='yes'
     fi
     if [ -z "$downloaded" ]; then
-        check_result $E_NOTEXIST "backup $backup doesn't exist"
+        check_result $E_NOTEXIST "backup file $backup doesn't exist in '${BACKUP}' folder"
     fi
 fi