Try this:
SELECT DISTINCT o.id, o.items
FROM orders AS o
INNER JOIN items AS i ON FIND_IN_SET(i.id, REPLACE(o.items, ' ', ''))
WHERE i.wishlist = 0 AND i.cost = 44800;
Check this SQL FIDDLE DEMO
OUTPUT
| ID | ITEMS |
|-----|------------|
| 154 | 375, 374 |
| 155 | 377 |
| 159 | 384 |
| 172 | 435 |
| 174 | 440 |
| 228 | 770, 769 |
| 229 | 775,841 |
| 230 | 777 |
| 528 | 1518, 1517 |