Questions & Answers about Ovo je privatna isprava.
Because ovo is a very common neuter demonstrative used in Croatian to mean this when you are identifying, presenting, or pointing something out in a general way.
In sentences like:
- Ovo je knjiga.
- Ovo je moja sestra.
- Ovo je privatna isprava.
ovo works like this/this thing/this here in English.
By contrast, ova would need to directly match a feminine noun:
- ova isprava = this document
So:
- Ovo je privatna isprava. = This is a private document.
- Ova isprava je privatna. = This document is private.
Both are correct, but they do not structure the idea in exactly the same way.