Volume Ratio is to compare current Volume with previous volume If Bullish candle with VR is > 1, it is indicating that Buying interest has increased. If Bullish candle with VR is < 1, it is indicating that Buying momentum is weak.
If Bearish candle with VR is > 1, it is indicating that Selling Pressure has increased. If Bearish candle with VR is < 1, it is indicating that Selling momentum is weak.
However, if VR is too big e.g above 4, it may indicated that Buying/Selling will climax soon