You should check out the GTX Magnatec 5W-40 or the Castrol Enduron Plus SAE 5W-40 which are both available in the Czech. The Magnatec is a semi synthetic and the Enduron Plus is a full synthetic.
Also check out the SYNTHOIL HIGH TECH 5 W-40, TOP TEC 4100 5 W-40 and the LEICHTLAUF HC 7 5 W-40...