No, not all truths can be scientifically verified. Take a self evident truth that is universally intuitively accepted as true like that it is wrong to lie and steal. What scientific verification is there for that? Take a historical event that is universally believed to have happened, what scientific verification is there that it took place? Science usually does not accept anecdotal evidence. Take something you know as true based on inference and life experience. e.g. Say you are walking on a trail in a forest and hear two people who you do not see walking and talking loudly behind you . You would know as a true fact afterwards that people were behind you even though there would be no way science could verify that for you. etc.