"He does not agree with himself."
Translation:Anh ấy không đồng ý với bản thân.
can someone explain what is wrong when i translate it this way " Anh ay khong tu minh dong y". This sentence is not acceptable. There is a sentence 'They want to cook pasta by themselves" translates as " Ho muon tu minh nau mi y".
That would mean "he doesn't himself agree" and it sounds quite weird as well. The last sentence you gave uses "tự" to mean "by themselves". So whenever you see: "X tự Y bản thân" it means "X are Ying by themselves, to themselves". "Tôi tự giúp bản thân" = I myself help myself.