develop the quality of
contribute to the high quality of
Since there is increasing involvement of bureaucracy in public education, private schools appears to enchant more resources from qualified teachers, outstanding students
You could end this sentence here. The next sentence starts with: Consequently, they all contribute to...
as the governmental budget is limited, meanwhile the number of students is accumulating over time,
due to the limited government budget and the increase in student numbers over time
having their children studying
having their children study
as the social rule for having cheating people money with low quality of teaching.
owing to low quality of teaching
hardly ever had any schools not been diminished
in tough competition toward
in competition with
private schools still present in education system are the elite ones which should be kept to contribute more.
This sentence sounds too complicated. You could express the idea in a simpler way: As such, I believe that private education should be continued.
Business and national corporations, at the same time, should also contribute more their revenue to this such important factor to the country development.
I don't think this sentence is relevant to the topic.