The issue was that when Vein Protection Elixir was available in the past, he was still striving to improve his cultivation, unsure if he could reach the realm of Qi Refining Great Perfection before turning 60.
If he were to use his spirit stones to purchase Vein Protection Elixir back then, it might have slowed down the speed of his cultivation advancement.
Therefore, he had not made preparations in advance.
Otherwise, he wouldn't be stuck in a situation where he just reached the zenith of Qi Refining and had no Vein Protection Elixir at his disposal.
"I only left with over two hundred spirit stones. I used up the spirit stones I've saved before coming here to replace my artifacts and spirit amulets..."
Upon Meng Guan's ask for spirit stones, He Song, after a moment of thought, told the truth.
Though he had more than 60,000 catties of spirit rice on him, he definitely couldn't touch them when in dire need of spirit stones.