If you notice that you have bad grip during wet conditions, then it is a matter of the tyres. Do you have the correct tyres for the season? For summer tyres you will need to have summer tyres or all-weather tyres. The tyres should be of high quality, not worn out (more than 4 mm tread depth) and have the correct tyre pressure. You can check tyre’s wet grip on the EU’s tyre label, to see how it compares to other tyres. If the tyres should have good wet grip and have the correct tyre pressure, they are probably worn out.