Availability of the relationships

Is this an API question?

Relationships are in one direction (from a source object to a target object; the source object is the one with the property value on it).  Depending upon what you're describing here, could it be that the relationship is in the other direction so not returned by some API search?

Sorry, this is a wrong forum section. this case is not related to API - it is general issue. 

But anyway, i am confusing because I can see all relationships but my colleague cannot with the same role.   

I moved it to the clients section.

I'm unsure from the details you've given.  It could be related to permissions on the target objects, perhaps?  Or some configuration setting somewhere?  Has this started happening recently?  If so then what's changed in the vault?

I found reason - I hope. Users have read access to the objects (objects are transferred from external database), but it was configured that they cannot see the name of this object type (permission of the object type). Interesting effect but understandable.