Exiles come home. War-displaced Japanese return from China. REPORTS FROM JAPAN

`PLEASE advise us if my family should stay in China or return to Japan and settle there,'' reads a letter from a Japanese woman in China. The woman, orphaned during World War II in Manchuria, lives there with her Chinese husband and children.

She contacted a Tokyo-based volunteer group called Niji no Kai (Rainbow Group), which provides assistance to the war-displaced returning to Japan - some after 40 years' absence.

``I know her feeling about this home country very well,'' says Cho Murakami, chairman of the Rainbow Group.

``But when I think about lots of difficulties she may go through here, I don't know which answer I should give.''

This year Japan marked the 43rd anniversary of the end of World War II.

But some 5,000 people, many women and children who were separated from their families during the war, are believed to remain in China.

The war is not yet over for these war-displaced people. And even those who have returned or plan to go back to Japan continue to worry about their life there.

Japan colonized Manchuria, the northeastern part of China, in 1932. For the next 13 years, many Japanese went to China to help develop agriculture and industry there.

But the chaos of the Japanese defeat and withdrawal left many women and children separated from their families.

Yukiko Otosaka was one of them. She married a local man and lived in China for nearly 30 years until she returned to Japan in 1974.

``I must not forget how well the Chinese people treated me, though I had fleas and lice all over,'' recalls Mrs. Otosaka, the 64-year-old mother of four children.

``But I always wanted to come back to this homeland. So I am really glad now.''

Since the normalization of the bilateral diplomatic relations in 1972, more than 2,600 Japanese have returned to this country - many of them only to find shocking cultural differences.

Highly developed Japan, with its modern buildings, its electricity- and gas-powered conveniences, seemed a world apart from the communities where they had been living - places where coal and firewood are still in use.

``I was so surprised...,'' says Otosaka with a laugh.

Each day was full of discoveries for the women, who had forgotten how they had lived 20 to 40 years before.

``Chinese people say `thank you' just once when someone does something for them,'' says Isami Suzuki, who also spent more than 20 years in China.

``But I found Japanese people say `thank you' for the same thing every time they see each other again.''

``Also, Chinese people have no idea of returning a favor when they receive a gift from others, while a Japanese, in giving a present, expects something to be returned,'' Otosaka adds.

Sometimes, these returnees' reactions, which are contrary to the Japanese custom and manners, bring about misunderstanding and distrust between the two ``Japanese.''

``I've heard Japanese criticizing returnees by saying, `Do Chinese people not work hard?''' says Otosaka.

``Chinese people may be slow in doing something and not punctual, compared with the Japanese.

``But I want those people to know that that's the way they are raised in China.''

``I understand we must obey the law and rules here,'' comments Koji Otosaka, Otosaka's son, who has lived in Japan since 1981.

``But it is impossible to change your way of life quickly. It will take a while to be able to adjust yourself naturally.''

Problems with the Japanese language make life much harder for the returnees. Many were frustrated to find that their language capabilities limited them to low-wage jobs involving physical labor.

For those who come back permanently, the Health and Welfare Ministry provides language lessons for about a year and programs to help people adjust to the current Japanese way of life. It also pays their transportation fee from China.

``With this system, I think the government is giving fairly good assistance to those returnees,'' says the ministry's Kyoichi Saito, who deals with the problems.

Some Japanese returnees see a larger problem than the language barrier and the cultural gap. ``It seems that the Japanese people does not want to have a heart-to-heart talk with us,'' remarks Koji Otosaka.

``It's not the language that matters. The point is whether a Japanese can recognize the two cultures in each returnee and accept both,'' argues Ryuji Yabuki, adviser to the China Returnees' Group, another volunteer organization like the Rainbow Group.

``No matter who they are - whether they be returnees from China, foreign students, or foreign workers in Japan - the problem is always the same,'' adds Hirohisa Nagano, who teaches Japanese to returnees.

``There is an invisible and unbreakable wall between the people from outside and the Japanese,'' he continues.

For the future, the number of returnees to Japan will probably be increasing. The Health and Welfare Ministry has roughly estimated that at least 700 more war-displaced people would come back with their families.