From K1 to K3, It is a bullish morning star pattern. K3 nearly close upon the downtrend line.
It seems that the long-term downtrend had been reversed here. The problem of the bear force is low supply pressure. K4 is a first test to the potential support, And it verified the lacking of supply.
If K4 successfully test the support for a second time and close upon the downtrend line, It will be a valuable place to open a tentative long-term position.