I'm sorry there hasn't been a good answer to this question yet. You might want to try asking r/askpsychology as this is really a question that can probably be best answered in more general terms.

I would suggest one of the first keywords to research would be the field of attachment disorders, which really looks closely at a lot of the challenges that face individuals that have had the strong attachments in their life broken at a young age, such as orphans, institutionalized kids, kids in foster care, or kids in boarding schools.

Among the challenges facing such children are challenges with future relationships, including challenges feeling connected to foster or adoptive parents, a sense of not belonging, as well as a range of learning disabilities that can be connected.

The abusive conditions that most Romanian orphans were held in around the end of the Ceaucescu regime (and afterwards) were definitely prime candidates for causing attachment disorders, regardless of whether or not the children were adopted to foreign countries and faced additional culture shock as well.

Out of the dozen Romanian orphans that I have known growing up in Canada, all have faced challenges in life, though again often quite different, in much the same way that residential school survivors often deal with their past in quite different ways. I say this as evidence that what you really need to study is something like attachment disorders as a whole, rather than trying to look at this specific historical instance of a traumatic situation for children.

Strangely enough, as a linguist who posts in r/askhistorians, this is a very important field to my work as a language teacher, as there is a lot of institutional trauma in the history of my community very similar to the experiences of children in orphanages, and understanding the various impacts of this trauma and how it can be combated is the focus of my PhD thesis work. For my work, understanding this has been a combination of understanding the history (specific common experiences) in order to get specific approaches to combating the trauma caused.

Now, with all this said, there are several very good articles on individual orphans' experiences. I especially enjoyed https://www.theguardian.com/news/2014/dec/10/-sp-ceausescus-children

And here's an article on some rehabilitation work that has been done - https://www.telegraph.co.uk/women/life/25-years-on-the-orphans-of-1990s-romania-saved-by-a-nurse-from-n/