Please specify your operating system details along with your shell.

mtime - modified time- time the file has been written / deleted from, displayed as Modify: ... using stat command against file.
ctime - creation time - time the file was created, displayed as Birth: .. using stat command against file (if maintained)
atime - access time - time the file was accessed, displayed as Access: .. using stat command against file (if maintained)

So trying those switches without understanding them, can delete a lot of stuff you probably do not want.

+4 is correct format, since +0 is 24 hours from the time find was executed.

Code:

user@host:~/files/sql$ date
Wed 22 Apr 2020 06:38:58 AM CEST
user@host:~/files/sql$ ls -lrt 
total 0
-rw-r--r-- 1 user user 0 Apr 17 16:00 workorders.sql
-rw-r--r-- 1 user user 0 Apr 22 06:18 wmweb_test.sql.gz

user@host:~/files/sql$ find /path/to/files/sql -type f -name "*.sql" -mtime +4 # nothing found, why ?

Lets look at the manual for -atime as it explains the rounding which happens on all time options :

Ok this makes is more clear, but how can i find what i want using GNU find ?

Code:

user@host:~/files/sql$ find /path/to/files/sql -daystart -type f -name "*.sql" -mtime +4
/path/to/files/sql/workorders.sql

If you are not using GNU find or need greater resolution from / to, that can be achived using touch with temporary files, and using -newer and ! -newer with find.
Forum is full of those examples, so use a search option please.

Hope that helps
Regards
Peasant.