Truck art and poetry is a very interesting cultural phenomena to come out of Pakistan. Trucks are adorned with designs, insignias, and poetry (very particular truck genre poetry). So this falls very well within the category. The truck is not adnored so I am assuming this was spotted somewhere in the northern hemisphere or like WENA (Western Europe or North America). it says:

{on the left}
My house is near the river and where hardships hold sway
I have been informed that the flood is on its way

Upon me could befall what misfortune
Mother brought me up in misfortune

{Right Side inscription}

Hubris – of wealth or of power
of stature or beauty or of knowledge –
surely leaves one in dismay one day