Two garbage trucks cruised slowly through the Southgate neighborhood of Glen Burnie yesterday, stopping every few feet so the policemen riding on the back could search through one more batch of trash, looking for any clue that might lead them to the slayer of three elementary school girls.

By yesterday evening, the search had covered hundred of homes, and turned up little of value. Anne Arundel County police were left with just one solid clue in the stabbing deaths of the three children: a leather sheath designed to hold a hunting knife with a five-inch blade.

The sheath was found in the same wooded area where police Monday morning found the bodies of 8-year-old Theresa Hogan, her 10-year-old sister Deborah Anne, and her neighbor and playmate, Ann Brzeszkiewicz, 8.

Two of the girls were stabbed more than 30 times in the back, while the third was stabbled about a dozen times, a spokesman for the Anne Arundel County police said yesterday. According to the autopsy report, none of the three had been sexually molested.

"All of the blows were struck very viciously, with very strong force," said Police Sgt. William Chaplin. The autopsy report indicated that the blade of the knife used was about five inches long.

More than 50 police officers from the county force and the State police spent Monday and yesterday first searching the woods with metal detectors then, in some cases, going slowly from house to house, trying to check out the dozens of telephone tips they had received since Monday.

"If we had a motive, we'd have something to work with," Sgt. Chaplin said yesterday. "But we just don't have a motive."

The three girls were last seen by a neighbor shortly after 7 p.m. Sunday, as they headed to the woods where many neighborhood children play in a makeshift forts. They were found Monday morning, fully clad, lying face down in a small muddy stream in the woods, a few hundreds yards from the homes.

"We're looking for a murder weapon, maybe bloodied clothing - or anything," said Anne Arundel County Det. John Inilekofer yesterday as he jumped off the back of a county garbage truck and sifted through one more bag of trash.

The only things of interest they had found, he said, was some paraphernalia used in the manufacture of the drug PCP - "but that's not what we're looking for," he added.

But the search for the killer yesterday was "the farthest thing from my mind," said Richard Hogan, the father of two of the slain girls. Hogan sat quietly in his living room most of the day yesterday, patiently accepting the questions of reporters and making plans for Thursday morning's funeral at the Holy Trinity Roman Catholic Church in Glen Burnie.

"Tonight will be our trauma time," said Hogan, explaining that he and his wife Ingrid planned to visit Singleton's funeral home to view the bodies of Debbie and Terry for the first time.

Hogan, a personnel specialist for the Calvert County Board of Education, moved to the Southgate neighborhood, about 12 miles south of Baltimore, just three years ago, after retiring as a lieutenant colonel and leaving Ft. Meade, where he had been stationed.

"One of the things we like here was that the house was not on a street that was heavily trafficked.It was a quiet area. You didn't have the whole city thing and it was near the school."

At the time the Hogans and their four children - Debbie, Terry, 13-year-old Michele and 4-year-old Ricky - moved into the Southgate community, all the older children were told "not to go too deep down there" in the woods, Hogan said yesterday.

Then, calmly, he told the story of Sunday night all over again: how the girls failed to come home by 8:30, how he called the Brzeszkiewicz home four doors down from his on Cross Creek Drive to see if they were still with Ann, how he said Jack Brzeszkiewicz went driving to all the children's normal playing spots, shining their flashlights and endlessly calling the children's names.

But when he recalled Debbie's planned flute recital, and the piano practices he had helped Terry with he lost his quiet composure for an instant. His wife, Ingrid, stayed in the kitchen, away from the flow of strangers and in the company of the relatives who arrived yesterday to be with the family.

Catching his breath for a brief instant, Hogan stopped, then reminisced once more about his family's search for a new home three years ago. "We looked at 79 different houses," he said ". . . we chose an area we thought was relatively safe."

Anne Arundel County police Capt. William Lindsey said yesterday that the Glen Burnie Moose Lodge has offered a $500 reward information leading to the capture of the killer.