I am demonstrating some examples where you can search for the right niche by using google search.

You can select a keyword, then search for topics under it based on popularity searches on google.

See the video below -

I am showing an example of searching for niche keywords for acne

If you wish to make a project on acne, use Google Wonder Wheel to search for keywords and niche topics.

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You can also see high quality video at Facebook.