How do you identify similar (but not identical) cells in Google Sheets?

I have a list of companies in Google Sheets.

I'd like to spot duplicates where the company names might not be identical.

For example, a company may be listed twice...

1. Once spelt correctly and once incorrectly.
2. Once as Acme Corp. and once as Acme Inc.
3. Once under its full name and once in abbreviated form.

How can you identify these?