How can I tell to the rule I am writing that the value of region field is the value coming from webform data?
If I switch to data selection I can't find submitted values, so how can I tell to the rule I am writing that the value of region field is the value coming from webform data?


You can use a technique similar to what is described in my answer to "How to do a data comparison to submitted webform data when using the Rules module?". For short:


Add an extra Rules Action to Add a variable (call it whatever you want), with a value assigned to it equal to your [data:ComponentFieldName-value-raw] (with a data type which equals the data type of your Webform component), and with ComponentFieldName whatever you're using for that region field in your Webform).
In your subsequent Rules Actions you can refer to the value of this variable you just added (that's the clue!).