We can plot single runs of an experiment as follows:
import cocopp
%matplotlib
# Load the data
dsl = cocopp.load(path_to_experiment_folder)
# Filter by dimension & function id
dim = 20
funcid = 1
ds = dsl.by('dim')[dim].by('funcId')[funcid][0]
# Plot
ds.plot()
# cocopp.config.mpl.pyplot.show() # if it doesn't show

Note: This usually does not show all evaluations, in particular, evaluations that did not hit the next target are not shown.