Office crush

I like this Chinese guy in the office. He knows that I like him. I text him like once a month with random stuff such as telling him that I like his smile, say good nights, etc. But I never receive a reply.He stares at me everyday. There's no day that our eyes won't meet. Also, when I pass by his cubicle I can see in my peripheral vision that he's looking at my direction. He seems to be always around.He has his group of guys friends. They're all young, like fresh university graduates. But I can sense that he has interest in guys with the way he stares at me. You know, the kind of looking deep into your soul.I'm really confused (no pun intended). I already tried to ask him through text if he wanted to talk but he never replied. Should I personally ask him? Should I wait a little longer? Or should I let him go?