I found an article that was written to help you solve the problem with a WordPress database. I had to modify the SQL queries to match my tables but it worked. It is an old article but still relevant advice. A snippet from the site and a link to the article.
A couple of example of what you might be seeing: â€œ' € â€™During the rush, apparently the most recent database backup file was somehow uncompressed outside of MySQL before final import.
Several days later, that decompression/unzipping basically converted every quotation mark, em dash, en dash, ellipses and other special characters into some really ugly-looking codes.
source: https://digwp.com/2011/07/clean-up-weir ... -database/
I hope this helps you.