Hi @Andriy Rudnyk,

As this guide outlines, while there may be a lot of properties that sync with a given event - think placed order event syncs the properties address, item name, item URL, item price, etc. - the ability to segment off of event properties has to do with how this data is structured. We are only able to segment off of top-level event properties. This could explain why you are unable to segment off of certain properties passing with an event. We can, however, still use the non top-level properties by pulling that data into an email template - think adding first name to an email. 

If you find that your inability to segment off of certain event properties is inhibiting your ability to execute a particular use case, you do have the option, with the support of a developer,  to pass custom events to Klaviyo. By doing this, you have full control over the event properties that pass as top-level properties. You can see if you are able to apply logic within your ecommerce platform to identify the matching billing/shipping address and then push to Klaviyo an event property associated with a specific purchase so that you know if the purchasewas for self or for another. You could then create segments off of this event property or use this property as a trigger filter in a flow to ensure different communication for either audience post purchase.

Hope this helps!

Julie