code required to find similar entries in two columns

Hi,
I am relatively new to using Excel with vast amounts of data and was after
any suggestions which could help me complete a problem that I have..

I have two columns with descriptions in (approximately 10 words). I need to
find descriptions from one column (Sheet 1,column C) which are similar to the
other column (Sheet 2,Column A).For example,if I could display the number of
words which are similar to both columns I could then find the ones with the
largest number of similar words.

For example, the two columns could look like...

Sheet1,column C....
Description
300g Fish fillets

Sheet2,column A
Description
Fish fingers 300g

This would then give the result that there were 2 similar words.

Any help would be much appreciated as to how to carry this out...