You can loop through the columns, and check and add 'RWS' columns. See the sample code:
import originpro as op
wks = op.find_sheet();
glayer = op.new_graph(template='box.otpu')[0]
for i in range(wks.cols):
if wks.get_label(i) == 'RWS':
plot = glayer.add_plot(wks, i)
James