brush - Adding a canvas texture on a drawing in photoshop

Hi, It’s a part of Simon Stalenhag’s work. when you look into it closely, you can see the texture behind colors. I thought he’s using a canvas textured brush but I think it’s not. When we use textured brush we can see the pattern of the texture but in his work I couldn’t find any texture pattern repeats. I was going to ask him directly in Twitter, but it seems like he blocked strangers to messaging him

How can I add this kind of texture on my drawing in photoshop? Can anyone give me some clue?