Iam not seeing any students in that room или i don't see any students in that room объясните почему, ?

I don't see, потому что глаголы восприятия  и выражения умственной деятельности (see, hear, think и т.д.) не изменяются в Present Continuous.
Исключение - некоторые случаи использования глаголов think и see: think - если означает "обдумывать", see - если означает "встречаться, иметь встречу". 

Many immigrants from the former USSR are great patriots of theUnited States, and these people sincerely love their new motherland. But theirfeeling of America is of a little strange kind; it is like a love of a parasiteworm to the body of its host. 

The way of life in the so-called Russian District in Brooklyn isvery interesting. I have seen different countries and never saw anythinglike this. If you think that such thing as culture of povertydoes not exist, I would strongly recommend observing li

1. Was he watching TV at 7 o'clock yesterday? 
Was he watching TV or DVD at 7 o'clock yesterday? 
He was watching TV at 7 o'clock yesterday, wasn't he? 
What was he watching at 7 o'clock yesterday? 
Who was watching TV at 7 o'clock yesterday?

2. Does the man play the piano every day? 
Does the man play the piano or the guitar every day? 
The man plays the piano every day, doesn't he? 
How often does the man play the piano? 
Who plays the piano every day?

3. Did we listen to the radio yesterday? 
Did we listen to the radio or watch TV yesterday? 
We listen to the radio yesterday, didn't we? 
When did we listen to the radio? 
Who listened to the radio yesterday?

4. Is she working in the garden now? 
Is she working or playing in the garden now? 
She is working in the garden now, isn't she? 
Where is she working now? 
Who is working in the garden now?