C197 Tang Tianhua's Reason

On the same day, Tang Tianhua finished collecting all the materials except for those that he didn't have.

However, he didn't intend to open the vault.

Instead, he went to his friends' place to see if they had the materials he needed.

Two days later, Tang Tianhua visited many of his friends and finally obtained some useful materials.

Unfortunately, there was still one that he didn't have