Sort( Table, Formula [, SortOrder ] )
SortByColumns( Table, ColumnName1 [, SortOrder1, ColumnName2, SortOrder2, ... ] )
either one works for sorting. Just substitute the ‘Table’ by your filter criteria. I this case created in the last 30 days. Note that SharePoint delegation plays a part in Search() so Filter() is usually preferred, combined with StartsWith().
Sort(
Filter(Table,
StartsWith(Title, Textbox1.Text),
Created > DateAdd(Today(), -30, Days)),
”Created”,
SortOrder.Descending
)