If you’re looking for a great non-American film from that period, I highly recommend Get Carter (1971). It’s a classic of the British gangster genre.
I agree and would add Z…a political thriller suddenly made somewhat more relevant to our times.
This website recommends a bunch of movies as being similar to Chinatown:
https://tastedive.com/like/Chinatown
It starts by recommending ten films. If you click on the square that says “MORE”, it recommends more of them. You can click on “MORE” four times before it runs out of movies to recommend. I’ve seen most of the movies it recommends, and they’re all reasonably good films. The question in the OP is, after all, pretty vague, and there’s no definitive answer to it.
Also Mildred Pierce, The Postman Always Rings Twice, and Double Indemnity. All from the James M. Cain novels.
Ask The Dust is from the John Fante book of the same name.