Pleasanton Police say they have searched all areas where missing runner Philip Kreycik could be

PLEASANTON, Calif. (KGO) -- Pleasanton Police went back into the East Bay hills Saturday to continue their search for missing runner Philip Kreycik.

The 38-year-old Berkeley man went for a run in Pleasanton Ridge Regional Park three weeks ago today and he hasn't been seen since.

Across the city of Pleasanton, you can't help but see the face of missing Berkeley runner Philip Kreycik.

RELATED: Search for missing Berkeley man Philip Kreycik continues this weekend in Pleasanton

Volunteers are still searching and expanding their coverage area of these posters into Dublin, Fremont and Castro Valley, hoping someone will see his face and have information.

But even after three weeks of constant work, his wife, two kids and parents are still waiting for that breakthrough.

"We're hopeful," Kreycik's father Keith Kreycik said. "We're still hopeful that things are going to turn around."

VIDEO: EXCLUSIVE: Wife, father of missing jogger plead for help saying, 'he's waiting for us'

The family of a missing runner spoke exclusively to ABC7 News, sharing their heartbreak, but also their hope that he's out there alive.

"We miss our son, so incredibly," Kreycik's mother Marcia Kreycik said. "He's a delightful person, he has such spirit and such love emanates from him. He is just a big hole that we need to have back."

Pleasanton Police pulled GPS data from search crews over the past three weeks and found new locations that they had not checked yet.

Saturday morning Law enforcement crews from 17 Bay Area agencies and more than 100 volunteers hit the trails again to comb through the new area, but still found nothing.

"So now we pretty much 100% covered where he could've been, should've been or would likely show up," Pleasanton Police Lt. Chris Niederhaus said.

RELATED: Volunteers continue search for missing runner in Pleasanton after authorities scale back efforts

The volunteer search effort will continue Sunday with drones and experienced hikers going back into the hills.

The group tells us they are facing a harsh reality, they just don't know where Philip Kreycik is.

"It's an incredible lonely journey," Kreycik's wife Jen Yao said. "But the support we have received, so much, has really made us feel less lonely in this just hard, incredibly difficult time."

With no new leads, investigators are still asking for the publics help.

If you have any information on Philip Kreycik, contact Pleasanton Police.