Brother!
This product claim to develop a certain coat on engine parts that will reduce the friction and i have also used this product and i believe the real results will come after you will run 1000 km
If your car gives you smoke and reduce oil than Liqui moly also have product name oil saver which is also available at Khan motors and its purpose it to lubricate different seals inside the engine and reduce oil consumtion as well.
I have use their produce oil saver as well and it is also very good product.
The basic receipe is clearly mention on their product that it should be 6 % of the oil and rest 94 % should be engine oil.
So for example ceratec if you car engine oil capacity is 4000 ml (4 Lt) than 6 % is 240 ml (4000X6 %) so you will add 3760 ml (3.76 lt) oil + 240 ml (.24 lt) Ceratec = 4000 ml (4lt). but i believe additional 60 ml dont make any difference.
But for cars using 2.5 ML engine oil this 300 ml can be used twice, so for cars in which engine capacity is 2.5 ml it is not recommended to add full (300 ML) bottle in engine oil.
Thanks
faizan