Edit text by font type within a given selection?

Mac OSX Mojave 10.14, LO Writer

I want to filter all text that has a certain font style within a selection, i.e. I want to select an area of a paragraph then filter all font of a certain size/style so it can be changed all at once.
I tried faffing about with find & replace but couldn’t manage to get the result I wanted. If this is indeed the method to use, please illustrate your answer with a few pics/explanation.


I don’t answer directly to your question.

filter all font of a certain size/style so it can be changed all at once

The sequence (eventually non contiguous) you describe and what you want to do calls for character style. You grant some specific meaning to the “words” highlighted in a "certain size/style. The best thing you can do is mark up these words with a custom character style if you don’t find what you’d like in the built-in styles. Mark the words while you type (or while you review your text). Every specific meaning or semantics should have its own style. Don’t think in decoration terms (bold, italics, colour, size, font face, …), thin only in what the words are for you. This is translated in the style name as Math, Architecture, Foreign word, Variable, Opinion, anything handy and speaking for you.

Then, and only then, modify the character styles so that the marked “words” stand out of surrounding context and can be identified as pertaining to a specific meaning

This is much more versatile and easier to maintain than direct formatting and tedious application of Find & Replace.

It may look as time-consuming the first time (and indeed it is when you do it reviewing your document) but afterwards there is some kind of magic in the way your document is tuned in a snap as all so styled occurrences are updated simultaneously.

If you repeatedly write similar documents, save your styles (paragraph, character, frame, page and list) in a template so that they’re immediately available in future documents.