How Title Sorting works on the MDL search page & how to search movies available for Netflix network

The titles on the search page can be sorted as shown in the picture.

I know that;

Let,

NOW = Total number of watchers

NOW|R = NOW who rate

NOW|R1 = NOW who rate for 1 star

NOW|R2 = NOW who rate for 2 star

So,

Most popular: NOW

Top rated: ratings, (NOW|R1 x 1 + NOW|R1.5 x 1.5 + ... + NOW|R5 x 5) / NOW|R

Recently added: date of the title's post added

My question is,

1. Can someone explain in detail how does the 'relevance' and 'top ranked' are sorted? Also, what are the differences between 'newest' and 'release date'?

2. I tried to search for movies that are available on Netflix, but only two titles come out which are BLACKPINK: Light Up the Sky (2020)  and The Forest of Love (2019). 

Search example: here

Also tried with other streaming services and some of them also not working. Is it because it is hard for MDL to integrate stuff between them or are there any other reasons for this?

EDIT: Question 2 is solved. Waiting for answers to question 1.