string count

Hi all,

I have data of following 

microsoft office 2007
microsoft office Excel 2007
microsoft office powerpoint 2007
microsoft office word 2007
microsoft office2010
microsoft office Excel 2010
microsoft office powerpoint 2010
microsoft office word 2010
7-bit
7-bit assd

.....

From above data I want to get total count of occurrence of Microsoft office, 7-bit likewise for all other sample.

I thank you in advance for, I hope, what quick answers there will be.

Thanks,

Vivek Singh