it's more about the depth of the topic coverage. Saying you're targeting the topic "is acrylic paint safe for skin?". Current top pages for the term might have covered subtopics like -
1. what is acrylic paint
2. acrylic paint ingredients
3. can you use acrylic paint on skin
4. other skin safe paints
Now, you can go ahead and cover the topic even deeper like -
1. what is acrylic paint (this part can be skipped and covered in a separate article)
2. acrylic paint ingredients that can potentially harm your skin
3. can you use acrylic paint on skin?
3.1. acrylic paint on face
3.2. acrylic paint on body
3.3. acrylic paint for finger painting
3.4. acrylic paint for baby handprint
4. can one be allergic to acrylic paint?
5. symptoms of acrylic paint allergy
6. how to remove acrylic paint from skin?
7. what paints you can use on your body and face
(this was a rough example made based on brief research)
also. doing research based on already ranking pages isn't always the best decision. There are forums almost in any niche. Plus, there is a discussion related to almost all types of things on quora. find these pages, and read peoples' honest opinions written without any intent, unlike blog posts which are written to make money.
I hope this helps.