In the attached file, navigate to the 'copy till end' bookmark and copy all the
text after this bookmark till the end of the line.

Then navigate to the 'replace from here' bookmark and select all the words till
the end of the line, the past the contents of the clipboard.

It appears that writer has a tendency to maintain the length of the line at
which the 'replace from here' bookmark lies, as a result since after the paste
operation the length of the line reduces, the previous and additional contents
of the lines reappear.

Scroll up and down, minimise, reload the doc (or in general do something that
hides the problematic text) etc... solves the problem.

This is a UI problem, which is seen at many places actually but I somehow, with
great difficulty, produced it here.

I think this is the reason for crumbled text, broken images and many other such
UI problems which usually cannot be reproduced at second attempt.

I'll try and take the snapshots and attach it here if other such UI problems occur.