Question: What is the 1st leg that has a 2nd leg of 0–0 of Olympique Khouribga?
SQL: SELECT "1st leg" FROM "2-14835821-4" WHERE "2nd leg" = '0–0' AND "Team 1" = 'Olympique Khouribga';

Question: What is the 1st leg of CS Sfaxien?
SQL: SELECT "1st leg" FROM "2-14835821-4" WHERE "Team 2" = 'CS Sfaxien';