HANOI, AUG. 3 -- Vietnam has promised to speed up its efforts to track down missing American servicemen and, in return, the United States has agreed to "address certain urgent humanitarian concerns of Vietnam," a joint communique said today.

According to a five-sentence statement released at the end of three days of talks on renewing the search for the nearly 1,800 Americans missing in action in the Vietnam war, "Specific measures were agreed upon to accelerate progress toward accounting for {the MIAs} and to address certain urgent humanitarian concerns of Vietnam."

The communique said experts from the two countries would meet "in the near future" to work out "the next steps" in locating the missing Americans and to discuss Vietnam's humanitarian concerns.

The statement gave no details about what these concerns might be and how the United States would address them.

Vietnamese officials have said recently that if the United States wants further help in locating its MIAs, Vietnam wants humanitarian aid for its war victims, including orphans, disabled people and alleged casualties of U.S. chemical warfare. The United States has steadfastly rejected "any attempt to trade information of our missing men for economic aid," as Secretary of State George P. Shultz put it last month.

Today's communique said both countries agreed that the MIA and humanitarian issues "should not be linked to broader political questions such as normalization {of diplomatic relations} or to economic aid."

Retired U.S. Army general John W. Vessey Jr., President Reagan's special envoy who headed a nine-member U.S. delegation, called the talks "detailed, candid and constructive" and described the trip as "worthwhile."

Vessey, a former chairman of the Joint Chiefs of Staff and combat soldier who was decorated for heroism in the Vietnam war, answered no other questions about the talks, saying he first had to brief Reagan on the agreements.

Vietnamese Foreign Minister Nguyen Co Thach, who headed the Vietnamese side of the discussions, said, "We are happy. We are satisfied," apparently referring to the U.S. side of the bargain.

Vietnam's cooperation in tracing the missing Americans came to a halt in the middle of last year. Hanoi had promised in mid-1985 to resolve the MIA problem in two years, but since last October it had not agreed to any further technical talks on the issue. No MIA remains have been returned to the United States in more than a year.