It's hard to expose when working on Google Ads Black Keyword

We are steadily progressing to raising the budget through account optimization.
And I can even hide black pages through cloaking.

I modified the advertisement title and description with the contents related to the black keyword, and inserted the black keyword as an extended keyword in the keyword.

However, the advertisement is normally approved, but it is not exposed well.
When I check it on my computer and phone, it doesn't expose me at all, but only the exposure graph goes up little by little.

How can this phenomenon be solved?