How to use PHP implementation similar to Baidu know similar problems recommended features

I would like to implement a function that is similar to Baidu know, ask questions, put similar issues to push out the function

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I would like to implement a function that is similar to Baidu know, ask questions, put similar issues to push out the function

This is related to the recommendation algorithm, I do not quite understand.
A simple way to do this is to add keyword tags and problem heat to each question (such as the number of answers, the number of followers to get a weighted value), and then display the same issues with the same tag.

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