Olive.. depends on what issues they have... some kids are not violent, they just need psychological help to overcome their psychological trauma, and they get this help gratefully. Some kids are just untethered. It is like a mentally sick person. You cannot do anything about it, but suffering to the rest of his (or your) life...
I mean to spend more time before taking the child home.. To visit him/her at orphanage, to take a kid for a walk, to the movies, for the shopping.. like a "dating" before "marriage". This should be a normal practice. We are not getting married for sake of marriage, right? we choose our life partner cafully, by dating, by getting knowing each other. Why potential parents have to adopt a child only based on papers and his photo? Mom has to LOVE her child, right? It should be mutual contact.. Otherwise it wil never work..