I would say one and the same. Being that the Czech CH is pronounced like a ch in Achtung and in English the CH could give a ch sound as in church or ch pronounced as a K.
It is all in pronounciation.
The city of Praha's phone book is listing the name PRUCHA in very good numbers.
http://phone.quick.cz CZ's phone site
http://mapy.atlas.cz for locating a town in CZ
www.csagsi.orgwww.cgsi.orgwww.ncsml.orgwww.slovaklinks.comwww.iarelative.comwww.rat.de/kuijsten/navigatorwww.czech-genealogy.com