MP4 : Why do we tend to have negative feelings?DOC : Why do we tend to have negative feelings?m3u8_240p : Why do we tend to have negative feelings?m3u8_360p : Why do we tend to have negative feelings?m3u8_240p : Why do we tend to have negative feelings?m3u8_480p : Why do we tend to have negative feelings?m3u8_480p : Why do we tend to have negative feelings?MP3 : Why do we tend to have negative feelings?m3u8_360p : Why do we tend to have negative feelings?