Someone has said that prayer is not about overcoming God's reluctance, but about laying hold of His willingness.
This can be said of healing also.
God's willingness to heal is seen in His Word, where He repeatedly revealed His desire to heal the people.
We can read healing scriptures out loud,
so that our eyes see them,
our mouths speak them,
our ears hear them,
our bodies feel them and
our minds perceive them.
More importantly, keep reading them and let the words penetrate into our heart and spirit.