What is the real purpose of the advance of the Crusaders to the East? What was the guise of this goal?

The real goal of the Crusader troops was land seizure and plunder. Large feudal lords in this war were only interested in profit. They were far from that great purpose of the church. Thus, very soon the Crusades turned into a war for gold and land. So at the very beginning, the first kingdoms of the crusaders were formed on the territory of the Muslim lands. But still, over time, these lands were lost.