differentiate between (someone or something and someone or something else)
1. to recognize the difference between people or things in any combination. (Usually refers to two entities.) In your painting, I cannot differentiate between the costume of the figure in front and the flowers in the background. Can't you differentiate between Billy and his brother? I can't differentiate between a donkey and a burro.
2. to establish or create the difference between people or things. Why don't you paint in some highlights to differentiate between the figure in the foreground and the flowers in the background?