This plugin fixes a reported bug in WooCommerce, where the data structure before and after v3 was changed, and it affected the WooCommerce searching on certain fields: https://wordpress.org/plugins/order-search-repair-for-woocommerce/
Here’s the bug report that I found: https://github.com/woocommerce/woocommerce/issues/14879
The problem is that I need to disable Ajax Search Pro for the correction to actually work.
To replicate the problem, you need a WooCommerce database that has gone through the v3 upgrade process, and then use the WooCommerce search field to search on a Customer Name. Our install would display a set of results, but the the data in the results list was blank, and clicking into a result would open up incorrect nodes.
I hope this is enough for you to recognize the problem. We’ve had to disable Ajax Search Pro on our Production site in order to allow our customer service reps to do their back-office work in WooCommerce.