Is pore care serum effective? Please recommend one.

I'm turning fifty soon, so I'm really worried about my sagging skin and enlarged pores.

The serum I am currently using is running out, so I need to buy a new one. Since I am buying one anyway, I thought I would take this opportunity to purchase a product that is more beneficial for pores.

Has anyone tried the Dong-A Pharmaceutical pore serum in the picture?

Lately, I've been planning to buy serums from pharmaceutical companies. I used to use a product from Chong Kun Dang, and I thought it was affordable and offered good value for money.

Since it's a pharmaceutical product, I feel like it would be better for my skin. Also, it feels gentle.

Please recommend any other good pore serums. I'm not sure how effective a pore serum can really be, but I do feel a difference when I use it compared to when I don't. Since autumn is coming soon, I think I should keep using it.

And do you use the pore serum right after the toner?

I use serum right after toner. I'm also wondering if there is a specific order in which to use it.