In Bokeh, line glyphs can be added to a figure using the line() method for a single line or multi_line() for multiple lines.

p1.line([1, 2, 3, 4], [3, 4, 5, 6], line_width=2)

p2.multi_line(
    pd.DataFrame([[1, 2, 3], [5, 6, 7]]), 
    pd.DataFrame([[3, 4, 5], [3, 2, 1]]), 
    color="blue"
)