Romain Grosjean has said that he has yet to show his "full potential" on the racetrack this season.
The Frenchman has secured a 10th and sixth-placed finish in the first two races of the 2013 Formula 1 season.
The Lotus driver told Autosport.com: "It's been a little frustrating as I don't think I've shown my full potential yet. The first two races were quite difficult for me and I would really like a weekend where I can show what myself and the team can do this season.
"We've got great potential, I just need to unlock it. Hopefully we'll find the key in China. It's been frustrating for me as sometimes the car gives me what I want and sometimes it doesn't, even if the conditions and set-up are very similar.
"I've been working closely with my engineers and we made good progress over the last race weekend. The car and the latest tyres seem to be very sensitive to having the balance exactly right so that's what we're focusing on."
The Chinese Grand Prix takes place next weekend.
