You can filter the Search datasource with the status that you want, like the code below.
Filter('WTRF Database',Status = statusControl.Selected.Value)
This is what it looks like when adding it to your code.
If(
!IsBlank(TextInput2_4.Text),
(Search(
Filter('WTRF Database',Status = statusControl.Selected.Value),
TextInput2_4.Text,
"Assigned_x0020_To_x0020_Job",
"Tool_x0020_Number_x0020_Text",
"WTRFNumber",
"Customer_x0020_Text"
)),
Sort(
'WTRF Database',
'Priority Order'.Value,
SortOrder.Ascending
)
)
