The United Nations only uses troops and trade embargoes to back the Declaration of Human Rights true or false?

This is false. They use troops wherever they deem that human rights were neglected or suppressed.

False.

The United Nations uses its peacekeeping forces as well as trade sanctions in response to international conflicts, not only in regard to human rights issues. For instance, UN sanctions against arms sales exist against a number of nations deemed to be security threats (such as Iran or North Korea). And, as publicized by the UN itself, peacekeeping forces may be used for purposes such as: monitoring a disputed border; providing security during elections, assisting in-country military personnel with training and support, assisting former adversaries in implementing peace agreements; that they have signed, etc.