If you could put a scan of the words/placenames you are looking for, it would help.
I originate from Ruabon and maybe I could recognose them from the handwriting. There were many variations used, For Example, Ruabon is used today You can find Rhiwabon, Rhuabon, Rhiwfabon - and of course the handwriting may be poor, or as someone else said, the person who was doing the recording was possibly not completely literate, and of course, many census enumerators had no knowledge of Welsh, or how to write it and would often just write down what to them was a phonetic spelling of a placename, or even person's name.
Rachel Bowen, France