$Code = "GOL"
This returns all the groups having "GOL" in their names:
Get-QADGroup "*$Code*"
This returns all the groups having _GOL_ in their names:
Get-QADGroup "*`_$Code`_*"
Both of these return nothing:
Get-ADGroup -Filter {Name -like '*$Code*'}
Get-ADGroup -Filter {(name -like "*$Code*")}