If you want to speed up temporarily when the cruise control is on, depress the accelerator pedal. Increased speed will not interfere with cruise control operation or change the set speed.
To return to the set speed, take your foot off the accelerator pedal.
Kia Cee'd JD Service Manual: Control Cable Components and components location
Components
1. Knob & Boots
2. Shift lever assembly
3. Shift cable
4. Select cable
5. Control cable retainer
...
Kia Cee'd JD Service Manual: Height Adjust Components and components location
Component Location
[5Door, Waggon only]
1. Height adjust
...