@ baohiep
About the ports: You can enter single ports or ranges in the tool like this for example.
If you pay the stream and you want to find out the port then use CMD tool with the command...
...to see all remotes / IP addresses / ports / status / PID.In this case port is 443 you can enter in the tool.
Now you can also use...
Code:
rtmpdump -r "rtmps://123.30.136.230:443/vod//Info/Toan2016/ProS/Gioi thieu/02.Khoa luyen thi THPTQG 2016.mp4" -T "abcd1234" | "player" -
greetz