There are so many things that science is yet to explain. Science is most concerned about getting substantial facts about anything, which is why it might take more time for science to give explanations for some things people see as mysteries. It is true that scientists have been able to develop theories for some phenomena, it is not yet certain how most of these phenomena occur.
For instance, scientists still find it hard to explain why people yawn, and not to talk of why yawning seems to be a contagious action. In fact, there are times you yawn by reading out the word "yawning." These and many other things are still mysteries that science has not explained yet.
However, the fact that there is no concrete scientific explanation for any of these does not mean science won't find it later. For instance, most of the things we considered as mysteries in the past are now scientific facts.