I'm a little confused as to why you're using a Condition action with a first() function straight after your Search for users call, that doesn't match the description on your issue.
If it were me, I'd be using the Filter array action to get that list broken down as need be and then you can work with it from there.
In my test below, you can see that I'm filtering based on the term Head Office in the returned array.

I have 3 users that it pulls back and two have the OfficeLocation property set to Head Office.
Before Filter
[
{
"Id": "c9692d85-ae00-470f-8544-4ded06082d59",
"AccountEnabled": true,
"BusinessPhones": [],
"DisplayName": "Automation",
"Mail": "automation@somewhere.com",
"MailNickname": "automation",
"OfficeLocation": "Head Office",
"UserPrincipalName": "automation@somewhere.com"
},
{
"Id": "8ddf4a13-fa28-4c76-8a79-dfcc680b57b9",
"AccountEnabled": true,
"BusinessPhones": [
"4251001000"
],
"DisplayName": "Joe Bloggs",
"GivenName": "Joe",
"Mail": "joe.bloggs@somewhere.com",
"MailNickname": "joe.bloggs",
"Surname": "Bloggs",
"UserPrincipalName": "joe.bloggs@somewhere.com"
},
{
"Id": "9d903297-2777-48d8-beb3-95e4e9ad2851",
"AccountEnabled": true,
"BusinessPhones": [],
"DisplayName": "Jane Doe",
"GivenName": "Jane",
"Mail": "jane.doe@somewhere.com",
"MailNickname": "jane.doe",
"OfficeLocation": "Head Office",
"Surname": "Doe",
"UserPrincipalName": "jane.doe@somewhere.com"
}
]
After Filter
[
{
"Id": "c9692d85-ae00-470f-8544-4ded06082d59",
"AccountEnabled": true,
"BusinessPhones": [],
"DisplayName": "Automation",
"Mail": "automation@somewhere.com",
"MailNickname": "automation",
"OfficeLocation": "Head Office",
"UserPrincipalName": "automation@somewhere.com"
},
{
"Id": "9d903297-2777-48d8-beb3-95e4e9ad2851",
"AccountEnabled": true,
"BusinessPhones": [],
"DisplayName": "Jane Doe",
"GivenName": "Jane",
"Mail": "jane.doe@somewhere.com",
"MailNickname": "jane.dow",
"OfficeLocation": "Head Office",
"Surname": "Doe",
"UserPrincipalName": "jane.doe@somewhere.com"
}
]