How to use MySQL LIKE in comma separated values

Question

I have a simple table names locations with 3 fields

ID      |   location    |   sub_location
------------------------------------------
1       |   loc1        |   sub1,another,sub3
2       |   loc2        |   test1,test

How can I get matching values from location or sub_location based on users input? In simple, user will enter few letters in a text box. I have to check if any matching value is there in location or sub_location. But the issue is that I have comma separated values in sub_location column. Each comma separated words should be considered as different values and the result should be single values. Imagine that user entered 'sub' as search term, then my query is something like this. But it will not work, and throws query error near to WHERE clause. Any idea?

SELECT ID, location, sub_location FROM locations WHERE location LIKE %sub% OR WHERE sub_location LIKE %sub%

Answer 1

select * from locations where (location = input) or
(sub_location like concat('%',input, ',%') or
sub_location like concat('%,',input, ',%') or
sub_location like concat('%,',input, '%') or
sub_location like concat('%',input, '%') )

Answer 2

SELECT ID, location, sub_location 
FROM locations 
WHERE location LIKE'%sub%' 
  OR sub_location LIKE '%sub%'

Without second Where clause just add OR