The men, who were armed with hammers or other blunt instruments, then ordered the women to get out and hand over their keys.
Ms Harwood has said since the carjacking she is very frightened about driving again.
She added: “I was terrified. They have got my house keys, purse, shopping, everything.
"I have had to get my locks changed. I am a district nurse and can’t work without my car.”
The second incident happened in Haxey Walk, Horwich, on Monday, July 14. A woman had pulled up outside a home in her white BMW 135.
She was pounced upon by armed robbers just after she had got out of the car with her young daughter.
Police are linking the incidents and say in both cases the robbers arrived in a small white or silvery grey car, driven by a third person.
The cars were found in Hindley after a resident raised the alarm about the vehicles on Sunday.
The cars are going to be returned to the owners after being forensically examined by police.
The robbers are still at large.
Anyone with information can call police on 0161 8565761 or Crimestoppers, anonymously, on 0800 555111.