Are the supplications reported from the Awliya (saints) and righteous individuals exclusive to them, or is it permissible for a Muslim to supplicate with them? And is it correct to specify certain verses and supplications for certain illnesses in Ruqyah Shar'iyyah (Islamic exorcision)?

The best forms of supplications (du'a), remembrances (dhikr), and incantations (ruqya) are those found in the Quran and Sunnah (definition). It is permissible for a Muslim to supplicate or incant with other supplications and incantations composed by others or by himself, as long as they do not contain shirk (definition) (polytheism) or violate Islamic law, or if the words are incomprehensible. Stories have been narrated about the righteous predecessors regarding ruqya for the evil eye. There is no objection to dedicating specific verses or supplications for the ruqya of certain illnesses, especially if this has been proven effective through the experience of the righteous predecessors.