照你的理解，原句应该改成

照你的理解，
原句应该改成：Her son is a lawyer, who is solving for himself the problem of a scholar in politics.
改得更好一点：Her son is a layer, who is solving for himself, in politics, the problem of a scholar.

原文里scholar前的定冠词告诉我们，这个in politics是修饰scholar的。