How did the Nixon doctrine different from the Truman doctrine?

Both Doctrines offered economic and military aid to countries.

Harry S. Truman proclaimed on March 12, 1947 that "it must be the policy of the United States to support free peoples who are resisting attempted subjugation by armed minorities or outside pressures....

In 1969 the Nixon Doctrine called for allied nations, especially in Asia, to take more responsibility for their own defense.

The English phrase 'truman doctrine' means President Truman's policy of providing economic and military aid to any country threatened by communism or totalitarian ideology

Truman made the Truman Doctrine because he believed that the US should rid the world of communism.