SQL - Find patrons with 2 last names

SELECT LENGTH(b.surname) - LENGTH(REPLACE(b.surname, ' ', ''))+1 as mycheck, b.surname, b.firstname, b.borrowernumber
FROM borrowers b
WHERE
	(SELECT LENGTH(b.surname) - LENGTH(REPLACE(b.surname, ' ', ''))+1)>1
	AND b.branchcode = 'RCPL'
    AND b.categorycode != 'ILL'
    AND b.dateexpiry >  <<Yesterday|date>>
ORDER BY b.surname