Queensland parents Lee and Allan Schulkins traveled thousands of miles, walked dirt roads, got lost in the bush and dragged an entire river with sonar in their desperate search for their daughter, who disappeared there six months ago.

The Fernvale couple have spent countless hours researching Amy Schulkins, 36, from information they’ve generated from the community, psychics and thousands of amateur sleuths online.

The 36-year-old mother of five was reported missing by wife Rebecca Schulkins after she failed to return to their home in Caboolture, north Brisbane, on December 30.

Police released CCTV footage of Ms Schulkins in her white Nissan Patrol, registered 257VTN, driving along Lower King Street in Caboolture just before midnight.

She was driving away from her home and her car was seen heading towards the Bruce Highway and Bribie Island interchange.

However, despite numerous reports and extensive research by the police and her parents, there have been no confirmed sightings of her.

Explore the state by boat, bike and car

The search for her parents is driven by the pain of not knowing what happened to their daughter.

Amy’s disappearance has devastated her parents, wife and loved ones, and their search has taken them across South East and West Queensland.

“We’ve probably traveled 30,000 to 40,000 kilometers in search since his disappearance,” Mr. Schulkins said.

“[We’ve done] couple days in the boat dragging all the Caboolture river with sonar looking for cars or anything underwater, in case something is in the water.

“I have spent countless hours on the bike and the 4×4 in the forest and the bush. We have searched everywhere you can hide a car.”

The couple believe the police are doing everything they can to help locate their daughter.

A car supposed to contain “a lot of clues”

Mr. Schulkins believes his daughter’s missing car contains clues to her disappearance.

“If we find the vehicle and Amy is in it, so be it. But we think the vehicle contains a lot of clues as well.”

Her parents are hopeful that their daughter is “gone and started a new life somewhere.”

In the hours leading up to her disappearance, Amy and his wife Rebecca had dinner with the Schulkins in Fernvale and left for Caboolture for the 90-minute ride around 6:30 p.m.

Once home, his wife said the couple sat outside with a drink and chatted.

“I was in [the] shower when she’s gone. We were sitting outside, had a few drinks and she was texting [a] friend on Facebook Messenger, ”Ms. Schulkins told ABC News.

Ms Schulkins said she read the messages and they were talking about Amy going to confront someone she knew about an issue from her past.

Police investigating Amy’s disappearance confirmed that she visited the person’s home, where there had been a confrontation, and then left.

Ms Schulkins said his wife had mental health issues and was diagnosed with a form of bipolar about two years ago.

“She’s bubbly. Amy lights up the room, people can’t help but smile at her. She’s just one of those beautiful souls,” she said.

“It was her outward appearance to everyone, but inside she was struggling.”

She said his wife, who was in therapy before his disappearance, was in a “different kind of mood” on the day of his disappearance.

“She was just in a bad mood,” Ms. Schulkins said.

She said she hoped that wherever she was, Amy would be safe.

Amy’s parents said they were very grateful for the tremendous support from the community that helped find her.

Online trolls cloud the investigation

Former Queensland detective turned private investigator Jason Gouge has joined the search.

Mr Gouge contacted the family to act pro bono in May after monitoring the search online.

He said part of his role in the investigation was to be the bridge between police and Amy’s parents, who were often inundated with information.

Mr Gouge said a Facebook page about Amy’s disappearance has attracted around 30,000 followers from around the world.

He said amateur sleuths were a help, but could sometimes be a hindrance.

“People upload great information, but others post misleading information,” Gouge said.

“Others offer relevant information.”

In one incident, police believe someone impersonated Amy on Facebook during a Missing Mom tribute concert.

“Police don’t believe this was posted from Amy’s Facebook account, but there have been a number of times people have produced fake accounts of her,” Gouge said.

He said his role in the investigation was not a reflection on the police, who were doing all they could.

Mr Gouge said a mobile billboard would help publicize Amy’s search from July 31, just before National Missing Persons Week.

The notice board was donated by the Missing Persons Advocacy Network (MPAN), a non-profit organization.

A spokesperson for the Queensland Police Department said investigations into the disappearance were continuing and asked anyone with information to contact CrimeStoppers on 1-800-333,000.