I visited many of non Hindu sites that they argue that Prophet Muhammad is mentioned in our(Hindu) scriptures and they mention some sloka , I find one sloka in Bhavishya Purana that they mention 
in above image and sloka line is महामद इति ख्यात:
they mention महामद as Prophet Muhammad but महामद is a Sanskrit word with its own meaning like
महामद mahAmada m. elephant in strong rut मजबूत लीक में हाथी
महामद mahAmada m. excessive or violent rut अत्यधिक या हिंसक लीक
महामद mahAmada m. fever महामद mahAmada m. great pride or intoxication(drunkenness) means मादकता and नशा
ख्यात: meaning
ख्यात khyAta adj. denominated नामित
ख्यात khyAta adj. told कहा था
ख्यात khyAta adj. well known अच्छी तरह से जाना जाता है
ख्यात khyAta adj. ppp. called कहा जाता है
ख्यात khyAta adj. ppp. celebrated मशहूर
ख्यात khyAta adj. ppp. notorious कुख्यात
ख्यात khyAta adj. ppp. well-known रूढ़
ख्यात khyAta adj. ppp. named नामित
महामद इति ख्यात: means who ()well known or called) as drunkenness (intoxication) or many other above describe meaning and it's not talking about prophet Muhammad! It is talking about mleccha म्लेच्छ
mleccha म्लेच्छ has own meaning
म्लेच्छ mleccha m. man of an outcast race एक निर्वासित जाति का आदमी
म्लेच्छ mleccha m. person who does not speak Sanskrit संस्कृत बात नहीं करता जो व्यक्ति म्लेच्छ mleccha m. foreigner अन्यदेशीय
म्लेच्छ mleccha m. barbarian असभ्य & जंगली , अशिष्ट, गँवारू, असंस्कृत म्लेच्छ mleccha m. non-Aryan गैर आर्यन
म्लेच्छ mleccha m. ignorance of Sanskrit संस्कृत की अज्ञानता who does not know Sanskrit
म्लेच्छ means who does not know Sanskrit or barbarian (असभ्य & जंगली , अशिष्ट, गँवारू, असंस्कृत) etc.. and धर्म means manner or nature ,that time no other religious exist so धर्म
धर्म dharma m. manner
धर्म dharma m. nature
धर्म so, म्लेच्छधर्म means barbarian manner or nature , अन्यदेशीय धर्म , जंगली nature (swabhav) etc above describe
So my question is why other religions(islam) argue that prophet Muhammad is in our scriptures ?
