The fact is spiritual healing is real and tangible among people of faith all over the World routinely. The main reason it does not work, is a true lack of faith or belief in the reality of God.
Hebrews 11:6
6 “But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him.
If there is a lack of acceptance of Jesus as your Savior
Romans 10:9
9 That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.
John 3:16
16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
Acts 4:12
12 Neither is there salvation in any other: for there is none other name under heaven given among men, whereby we must be saved.
If there is no acceptance of the requirements or no applications of these requirements, you cannot to receive the manifestation of a spiritual healing.
The requirements beyond believing in God and the acceptance of Jesus, is the confession of ones sins to the Lord.
1 John 1:9
9 “If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness”.
Forgiveness, you must not have any un-forgiveness in your heart towards anyone.
Mark 11:25-26
25 “And when ye stand praying, forgive, if ye have ought against any: that your Father also which is in heaven may forgive you your trespasses.
26 But if ye do not forgive, neither will your Father which is in heaven forgive your trespasses”.
Finally, you have to ask for what you want and then you have to believe it in the moment you ask God. Not before or after, but during.
Mark 11:24
24 “Therefore I say unto you, What things soever ye desire, when ye pray, believe that ye receive them, and ye shall have them”.
With respect to the prayer, you must not ask over and over again for the same thing, because that would not be a prayer of faith, it would be a prayer of doubt.
Matthew 6:7-8
7 But when ye pray, use not vain repetitions, as the heathen do: for they think that they shall be heard for their much speaking.
8 Be not ye therefore like unto them: for your Father knoweth what things ye have need of, before ye ask him.
Once you pray initially, you simply thank the Lord and believe you receive the healing until it happens. This is referred to as the prayer of thanksgiving.
Example: “Father I thank you, I believe I receive my healing in Jesus name”.
This is the process, and no person can tell if you have complied with any of this, its between you and God alone, but if you do, your healing will happen.
There are millions all over the world who experience this truth in their lives which tells us this is real, if you can receive it, you can too.