sometime after I started my car, i could not change tranmision, it sturcked (I cannot move shift stick). Then i had to turn my car off and started it again. there was wird sound from my clutch too. (In case i still cannot change it, i have to turn it off again and agin untill i can. )
Moreover during I drove my car when i put clutch it made some weird sound sometime.
And Yesterday I checked clutch fulid I found that it decreased than Min. then i took my car to check there was no leak
What happen to my clutch? How to check it? It is possible I have to change my clutch?

you can check the linkage from the shift lever down to the transmission. there must be some disconnected lines.

regarding the 2nd issue, it may be possible that by refilling the clutch fluid may cure the problem. or you can also check if your clutch assembly is defective.

sounds like your clutch isnt disengaging, possibly b/c there isnt enough fluid to push the slave cylinder all the way open, check the slave cylinder and the master cylinder for leakage, those are the main failpoints.....

I changed master and sleave already..but now it still has weird sound sometime when car start moving during i release pedal..why

maybe your throwout bearing is going bad, have you had the clutch replaced recently? if you did, did you change the throwout bearing?

i HAVENPT DONE clutch replacing, so it is time to do it ? i don't know when i should do it course the previouse owner did tell me anything about when he replaced it

try to do this, get on level ground, push in the clutch and put the car in first gear, let go of the brakes, tell us if the car rolls forward or not

It goes normally, so what I have to do?