Secretary of State Cyrus vance said after meeting Chinese Communist party Chairman Hua Kuo-feng today that his four-day visit to China had helped improve communication between the countries, but he indicated no breakthrough on the crucial issue of Taiwan.

Vance declined several opportunities offered by reporters at a press conference following the farewell banquet tonight to say that his trip had produced progress toward full diplomatic relations between the United States and China. But he and his aides signaled their pleasure at his high level reception from the Chinese, particularly the 1 1/2 hour meeting today with Hua, which was his first with a U.S. official since he succeeded the late Chairman Mao Tse-tung in October.

"I believe that our discussions were important in establishing effective communication between senior officers will continue in the future," Vance said at the press conference. "Our talks enhanced our mutual understanding of our respective positions on a wide range of issues . . . I look forward to continuing our discussions."

The four days of secret talks, good eating, sight-seeing and shopping left the firm impression that Peking would let President Carter's administration work out a way to persuade Congress that Taiwan would not be vulnerable to invasion if Washington removed its troops from the Nationalist Chinese island and transferred the U.S. ambassador to Peking, as Peking demands to establish normal relations.

As Hua's meeting with Vance began today in the Great Hall of the people, the Communist Party leader and premier personally endorsed Vance's cautious statements that the China trip was only an "exploratory" mission with no major agreements expected.

"We also think it is good for the new Carter administration to send someone here to explore China and get to know the leaders of China and to explore the development of the situation in China to get to have an understanding of China's views of the international situation and bilateral issues and to have an exchange of views," that soft-spoken Hua said. "We think that such an exploration is good."

Vance had reportedly sought clarification of the Chinese attitude on policies such as continued sale of arms to Taiwan if all formal ties are cut with the island. Asked if he now understood Peking's position on such matters, Vance said "I believe I do."

He declined to describe any specific discussion that took place during his 12 1/2 hours of talks with Chinese Foreign Minister Huang Hua, Vice Premier Teng Hsio-ping and Hua, saying he wanted first to report personally to Carter.

Vance indicated that he had told the Chinese of the need for some kind of congressional approval of normalization and of reluctance on Capitol Hill to jettison the mutual-defense treaty with Taiwan immediately.

Chinese officials have seemed unaware in the past of the carter administration's need to get congress approval for such a drastic move could rile conservative voters.

"I discussed at some length the mestic situation in the United States in general terms, our relationship with Congress, the changes that had occured over the last year and a [WORD ILLEGIBLE] or so," Vance said. "I think this was useful discussio from the china standpoint to hear firsthand what [WORDS ILLEGIBLE] States are, of those who represent the people of the United States in the Congress."

Asked if he still believes in Carter's recent suggestion that normalization might come before 1979, Vance said "I wouldn't wish to contradict the President in any way."

Vance said the two sides had discussed issues such as cultural exchanges, trade and the problem of old U.S. claims on property in China and Chinese assets frozen in American banks. He gave no indication of any progress but said, "Talks will continue."

Vance met Hua, who also has a brand-new administration that must communicate its particular desires to the Americans, late this afternoon in a mammoth reception hall.

Joining Vance in his talks with Hua were Leonard Woodcock, chief of the U.S. liaison office here; Philip Habib, under secretary of state for political affairs; and Richard Holbrooke, assistant Secretary for East Asian and Pacific affairs.

On his way home Friday, the secretary is to stop in Tokyo to discuss the talks with Japanese leaders, who fear that normalization may hurt Japanese investments on Taiwan. Vance said Holbrooke is flying to South Korea and Taiwan to brief leaders there on the talks.