回复：我和她在大学的时候就指出过她的学习方法了

How are you so sure that your method is the better one and the most efficient way?
Everyone is different in certain ways. The "most efficient" way may not suit everyone. People get used to doing things in certain ways. Even if your method is better, it will take them way to learn and adapt the new ways and they may not necessarily find it helpful.
I understand you are trying to help. However, you can't force others to accept your help.