It's not working because "what" is a "stopword" ...

from https://dev.mysql.com/doc/refman/5.7/en/fulltext-stopwords.html

It's not working because "what" is a "stopword" ...

from https://dev.mysql.com/doc/refman/5.7/en/fulltext-stopwords.html

I followed the instructions and created a new stopword list.

create table test.custom_stopwords as
select * FROM INFORMATION_SCHEMA.INNODB_FT_DEFAULT_STOPWORD
where length(value) = 1;

SET GLOBAL innodb_ft_server_stopword_table = 'test/custom_stopwords';

Then I rebuilt the fulltext index and it worked with the word "what."