Idk, I've read some good ones and some bad ones. My favorites are "Thinking, Fast and Slow" and "Making it Stick". Not totally sure if those fall under the "self help" category.
Any books where the author is actively selling a service, like consulting or training, assume that the book is just a glorified Infomercial in written form. Unfortunately that is like 90% of these books.
My problem with self help books is what they teach feels basic, and we tend to reject basic ideas (even if they may help us) so may I ask what your main takeaways from your books were, do they feel basic?