Hi,
I’m trying to use a corrector to split words from a book I got in text. I guess it’s a scanned book. No problems with line breaks.
Example:
This text hastwo words joined.
How would I reformat the text to split these? It makes reading close to impossible.
If you really expect some help, edit your question (= modify it; this site is not a forum; posts remain editable) to give more information.
Basics: OS name, LO version and save format
Specifics:
What is your starting point? A plain text file from OCR? What is inside? Runs of characters representing full paragraphs with a single linebreak at end or a set of lines with each a linebreak, eventually with a double linebreak at end of paragraph?
Is the lack of space separation between words a consequence of some processing of yours?
At which step in your procedure do you use Writer? What for?
What is your ultimate goal?
Don’t answer all these questions with a comment but be kind enough to reword your post.
I did my best. It’s just a book with this fluke coming from some sort of processing. I want to fix my book, so it’s readable 
You didn’t answer the questions. Do you start from a .txt file? If so, does the text editor in your OS access the OS spellcheck service?
You can also try to process the file with Writer Tools>Spelling which will detect such defects and propose a correction.
OCR doesn’t normally offer misspelt words. The time to prevent this was during the Find & Replace for Line breaks, they needed to be replaced by a space.
As it is now misspellings you have to use the spell checker, Tools > Spelling (F7) to find them and offer possible corrections.