arcgis 10.3 - Changing part of text element using ArcPy?

I work with multi MXD, and the title in all of them start with "The plan on the" and then i write the map's subject, for example:

"The plan on the land use", etc. I need to change just the sentence from "The plan on the" into "The blueprint on the". All other words in the title will remain the same. I try using this code:

import arcpy

from arcpy import env 

env.workspace = r"D:\desktop\Project"
for mxdname in arcpy.ListFiles("*.mxd"):
    print mxdname
    mxd = arcpy.mapping.MapDocument(r"D:\desktop\Project\\" + mxdname)
        for elm in arcpy.mapping.ListLayoutElements(mxd, "TEXT_ELEMENT"):
        if elm.text == 'The plan on the*': 
            elm.text = 'The blueprint on the*'
            print 'elm.text'

    mxd.save()   
del mxd

but it only print the MXD name:

>>> 
airplane noise.mxd
airplane noise2 a3.mxd
antiquities.mxd
conflicts.mxd
project.mxd

>>>