Vietnam today completed a remarkable five-day performance that it hopes will convince the world that normal relations with the United States may be just around the corner.

Hanoi's uncharacteristically soothing outpouring of words produced little evidence of a change in basic policy on the key issues dividing the two countries. But it won Hanoi some friends in the U.S. Congress and gave Vietnam's leaders a worldwide audience through the foreign news media.

Members of this capital's diplomatic community said they had never seen anything quite like it before. Several noncommunist diplomats credited the Hanoi government with making an important propaganda coup and said it represented the government's effort to get out from under the black cloud brought by its Cambodian invasion and export of refugees. $&(WORD ILLEGIBLE $&)See VIETNAM, A7, Col. 3> $&(WORD ILLEGIBLE $&)VIETNAM, From A1>

The second of two U.S. congressional delegations, headed by Rep. Lester Wolff (D-N.Y.), flew from Hanoi today with some of its members hailing a new climate. Another delegation led by Rep. Benjamin Rosenthal (D-N.Y.) left Friday. Together, the 22 members of the two delegations represented the largest contingent of Americans to visit this capital since the war ended in 1975.

As they left, this was the scoreboard on major issues:

The Vietnamese stood fast and refused to commit themselves anytime soon to a withdrawal of their troops from Cambodia, although they dropped a few hints that a partial pullback might be made sometime.

They hinted more information might be forthcoming on U.S. servicemen listed as missing in action. In Bangkok, his first stop after leaving here, Wolff announced that Vietnam had agreed tentatively to allow a U.S. officer be identified as Lt. Col. Paul Mather come to Hanoi to help trace the missing servicemen.

Hanoi promised to accept American officials as part of a U.N. refugee-processing team, but declined to say exactly what those officials would be allowed to do.

The meetings also introduced a new spokesman for the government, in Secretary of State for Foreign Affairs Nguyen Co Thach, who was given unprecedented access to both media and congressment.Affable and skillful with both, he put a smiling face on a government that has been pilloried for aggression against both refugees and Cambodians.

In one stretch he gave 2 1/2 hours worth of interviews, and his messages were unfailingly soothing. Vietnam would get out of Cambodia - eventually.It would not invade Thailand. The flow of refugees was being cut to a minimum. It was alright for the U.S. 7th Fleet to cruise offshore if the United States would just tone down the publicity, which was luring out more and more refugees.

"There is no war now," he assured Rosenthal. "It was only under Johnson and Nixon. There is no hate. We can meet on friendly terms."

The show delighted his government colleagues. One Vietnamese observed that the biggest single change of the week was the Foreign Ministry's willingness to go public with interviews.

"Now they realize that propaganda is just as important as anything else they have to do," this official said, referring to the Foreign Ministry.

Congressmen and reporters were asked persistently to predict when normal relations with the United Staets would be established, despite the State Department's insistence that it is not interested in talks now.

One congressman reminded his questioner, "You weren't interested in normalization a year ago."

The Foreign Ministry aide replied, "We make mistakes, you make mistakes."

The effect on some congressmen was considerable. Wolff noted the absence of polemics. Admitting that he did not know the reason for the "thaw," Wolff declared, "I'm glad of it."

Thach even told Wolff's committee that he felt he was helping Congress reassert its role in foreign affairs by inviting the committees here.

Several noncommunist diplomats saw the five-day effort as an international publicity coup for Vietnam. One said that government officials had portrayed the arrival of the two committees and the large press corps as a victory in itsefl. Another said that Vietnamese leaders, accustomed to a favorable national image as a spunky underdog, were trying to regain some stature lost by the Cambodian invasion.

"They have been pictured as aggressors on the Cambodian and refugee issues," the diplomat said. "They won a victory at Geneva [by promising to curb the refugee exodus] and now they're winning another one here today."