Vietnamese hairdresser Nguyen Thi Diem Huong, 24, is on her second trip to Singapore. And it is not for the food. She is here to find a husband.

But after more than a month of sitting and waiting daily at the True Love Vietnam Brides Matchmaker at Orchard Plaza, Miss Diem Huong is still unmarried.

In halting Mandarin, she said: "I am still waiting for the right man. I will leave it to fate."

She has about a month left before her visa expires. If she does not find a suitable man by then, she plans to return next year for another shot at marrying a Singaporean.

Vietnamese women like Miss Diem Huong who wait for husbands at bride agencies here are an increasingly uncommon sight.

GOLDEN DAYS Ten years ago, the demand for Vietnam brides was very hot. Many men walked into my shop every day and some even chose a bride within five minutes of seeing them. '' MR SIMON SIM, the boss of Mayle Marriage Agency.

In the past few years, some of the Vietnamese husband seekers have not made it past immigration checks at Changi Airport, say matchmakers. These agents make a loss on every woman denied entry into Singapore and put on a plane back to Vietnam, as they had paid for them to come.

Mr Francis Toh of First Overseas International Matchmaker said that in the past few years, up to half the women he flies here have not made it past immigration.

True Love Vietnam Brides Matchmaker's Mr Mark Lin said he now asks only Vietnamese women with relatives in Singapore to come, as he feels they are more likely to clear the immigration checks.

When asked, the Immigration and Checkpoints Authority (ICA) spokesman said: "Every visitor's entry into Singapore is neither a right nor automatic, and each entry is considered on its own merits."

The spokesman added that visitors may be put through interviews and additional checks, and those who are not eligible for a visit pass are refused entry and repatriated.

The Sunday Times understands that those denied entry were caught using a forged passport or had assumed a fake identity, as they may have been blacklisted from entering Singapore for committing an offence here previously. To enhance security at checkpoints, the ICA introduced a new BioScreen system in April to verify visitors' identities using their thumbprints.

Vietnam newspaper Thanh Nien News reported that in the first seven months of last year, about 2,000 Vietnamese passengers of VietJet Air and Jetstar Pacific were refused entry at Changi Airport, and the two airlines had to fly their passengers back to Vietnam.

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Matchmakers say the difficulties some women face in getting past immigration checks, coupled with the bad press surrounding quickie marriages gone sour, have put a big dent on their business.

A decade ago, they were the talk of the town, catering to blue-collar bachelors who sought love overseas after having had no luck with Singaporean women.

The first agencies promoting young, submissive and virgin Vietnamese brides sprouted up in Singapore around 2000. These Vietnamese women often do not speak English or Mandarin when the couple first meet, yet most tie the knot after a few meetings.

From a peak of more than 20 agencies in the middle of the last decade, only about half a dozen are still in business. The Golden Mile Tower in Beach Road, which used to house about a dozen Vietnamese-bride agencies, now has just three left.

One of them is Mayle Marriage Agency. Its boss Simon Sim said: "Ten years ago, the demand for Vietnam brides was very hot. Many men walked into my shop every day and some even chose a bride within five minutes of seeing them."

But now, there are rarely any walk-ins, and business is a pitiful fraction of what it was, he said.

First Overseas' Mr Toh has the same lament. In fact, he is looking for a part-time job to keep afloat. He used to arrange at least 20 to 30 weddings a year a decade ago, but does fewer than 10 a year now.

Matchmakers say stories of Vietnamese wives who ran away shortly after the wedding as they could not adapt to married life here, or women moonlighting in the vice trade, have cast a bad light on Vietnamese women in general.

Besides, prospective grooms are now bypassing the matchmakers, who charge up to $8,000 to find them a wife.

With many Singaporeans wed to Vietnamese women in the past decade, some of these Vietnamese wives are introducing their compatriots to interested men on the side without setting up shop.

Those in the know say these women usually get up to $2,000 for a red packet, which covers the prospective bride's airfare to Singapore and the introduction fee.