And nothing stops Us from sending signs (miracles) only because the men of former generations treated them as false. For example, We sent the she-camel to the people of Thamud – a manifest sign – but they laid violent hands on her. We send the signs only by way of warning, and if people reject the sign after receiving it, they are doomed.
Meaning:-
False: not true, based on mistaken ideas.
Manifest: to make clear or obvious to the eye or mind or the understanding; show plainly
Doomed: likely to have an unfortunate and inescapable outcome; ill-fated.