def search(request):
    try:
        search_term = request.POST['search']
    except (KeyError):
        msg = "You need to enter a search term"
        return render_to_response('chemicals/error.html', {'msg':msg})
    else:
        search_terms = request.POST['search'].split(' ')
        chemicals = Chemical.objects.all()
        for term in search_terms:
            try:
                chemicals = Chemical.objects.get(Q(weight__contains = term) | Q(cas__contains = term) |
                                                 Q(name__contains = term) | Q(id__contains = term) |
                                                 Q(structure_smiles__contains = term))
            except (Chemical.DoesNotExist):
                pass


        return render_to_response('chemicals/search.html', {'chemicals': chemicals, 'search_term':search_term})