Wisdom knows what is true, and how to use that information.  Worldly wisdom is based either on 'progressive wisdom' (building on the experiences and understanding of the past), 'inspirational wisdom' (a sudden awareness or 'eureka moment') or 'collective wisdom' (used in committees or teams). It is generated by humans for humans.   But God's wisdom cannot be unravelled using any of those methods.  He keeps to Himself all that we do not need to know, but reveals enough so that we know how to work with Him obediently (Deuteronomy 29:29).

Understanding anything requires an open mind which is willing to ask simple questions.  Paul was explaining that God's logic and wisdom was different from the corrupted wisdom of the world, so he asked, "Who knows what somebody is thinking?"  The obvious answer is – only the person who is thinking.  In the same way, nobody can know what God is thinking, except God.

The human race has an inbuilt blindness (2 Corinthians 4:4), thinking that we are better than we are; and as believers in Jesus we can fall into the same trap.  We may presume a greater spiritual wisdom than is true.  The Corinthian church was like that and it had become a den of ungodly spiritual arrogance.  Yes, they were in Christ, but behaved much as they did before they were saved, but with a spiritual gloss.

Despite their worldly habits and spiritual misunderstandings, the believers in Corinth had been blessed by God.  They had received the gospel message and had started to function as a local church.  Although they may not have always appreciated the ministry of Paul and Apollos, they had spiritually benefitted from both of them.  But neither needed praise from the church.  Their reward was with the Lord and would be revealed when He returns. Jesus spoke about that in Matthew 6:2-4, 5-6, 16-17.