I use two methods these days bro:
1. Google “Search”
I take a line from our article and search them on Google using double quotes " ". By this, I can easily figure out the websites which copied our content, here, this website took our paragraph and gave credits, I was able to find this easily.
2. Grammarly Premium
Grammary Premium has this plagiarism checker. This feature is really handy.
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