SELECT ob1.oID, ob1.vytvorena, os1.jmeno, za1.jmeno
FROM test.Objednavka ob1
JOIN test.Osoba os1 ON ob1.uID = os1.uID AND os1.zeme IN ('Great Britain', 'Germany')
JOIN test.Polozka pl1 ON pl1.oID = ob1.oID
JOIN test.Zbozi zb1 ON zb1.zID = pl1.zID
JOIN test.Zamestnanec za1 ON za1.zaID =ob1.zaID
WHERE zb1.kategorie = ALL(
    SELECT zb2.kategorie
    FROM test.Objednavka ob2
    JOIN test.Polozka pl2 ON pl2.oID = ob2.oID
    JOIN test.Zbozi zb2 ON zb2.zID = pl2.zID
    WHERE ob2.oID = ob1.oID
    )