What advice does Major Wolchek give Major Monet in the novel, The Ugly American?

When the legionnaires keep losing their skirmishes with the communists, Major Wolchek advises Monet to study the works of Mao Tse-tung, since Mao describes a new kind of warfare. As a proud Frenchman, Monet is reluctant at first, but he later realizes the value in Wolchek's advice.