For if that first covenant had been faultless - see the note on Hebrews 7:11. It is implied here that God had said that that covenant was not perfect or faultless. The meaning is not that that first covenant made under Moses had any real faults - or inculcated what was wrong, but that it did not contain the ample provision for the pardon of sin and the salvation of the soul which was desirable. It was merely “preparatory” to the gospel.
Then should no place have been sought for the second - There could not have been - inasmuch as in that case it would have been impossible to have bettered it, and any change would have been only for the worse.