What is hidden is hidden until you find it or it comes to you..
These boats were hidden for the those who travel by the car on the bridge because they are just under the bridge.To the passers by who walk or cycle to this location,they can see the boats but they could not see the intricate and delicate wood carving unless they come near.
However,only those with knowledge of the subject matter will know and appreciate its beauty!
All these are hijabs or the veils that hide things or truths from us.
Similarly if you are looking for someone.He or she may be right under your nose, but your ego or prejudice hide him or her away.Sometimes, a fake one has captured your whole attention preventing you from seeing the real one.Similarly,if you are looking for the truth.
From my personal experience,something was hidden from me for about ten years because Allah wanted to keep that for my needs on rainy days..and when the time has arrived, two strangers met one another,and a few months later they got married.C'est la vie..