Help playing separate audio/video files MKV

[Doomsday2010]

In advanced open file > I selected audio first (when I select video first > "play another media..." and the audio it doesn't open at all), then "play another media..." for the video > select Open and it works fine except I can't skip to different parts cause the video doesn't change but the audio is wherever I jumped to. If there's a more simple way to watch separate audio and video files I'd appreciate if someone enlightened me. Also if there was a way to simply combine the two somehow. Thanks for anyone's help.