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Your module is almost identical to the one in this question.
@pipe counted 35 segments...
With 6 pins, up to 30 LEDs can be Charlieplexed - not enough.
With 7 pins, up to 42 LEDs can be Charlieplexed.
...so Charlieplexing seems most likely.
Unless you can find the datasheet, a bit of trial and error will yield how the segments are connected. Use a 5V supply and a resistor (say, 1K), and connect each pair of pins in turn (all pairs, all polarities), noting down which segment lights up.
[This answer was written before the OP posted the front view of the display.]
A four-digit seven-segment display will normally have four multiplexed digits. This will require eleven pins and twelve if it has decimal points.
Figure 1. Common anode and common cathode 7-segment displays.
Figure 2. Each digit in a seven-segment display has eight pins for the segments and one for the common anode or cathode. (This circuit uses common cathode type.) Source: 7-segment display basics.
It seems very unlikely that you have a 4 x 7-segment display in your photo.