Number Game

You are playing a game with your friend. Your friend chooses three distinct numbers from the set (1, 2, 3, 4, 5, 6, 7, 8, 9). You will call four distinct numbers from the same set in each turn, and he will tell you how many of them are among the chosen numbers.

In order to guarantee to find these numbers in all cases, how many turns are needed?

Note: Naming these three numbers after your 4-number calls are finished does not count as a turn

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