I need some major help.

I have a spreadsheet with around 28000 rows. In Columns C and D, there are
two different lists. Each column has text that should match. For example in
Column C it might say "sprockets," and in Column D it would say "Sprockets
and Space Company." Then another row might say "engines," yet in Column D it
would say the same "Sprockets and Space Company."

I want to eliminate the rows that would obviously not match up like the
latter example, and keep the ones that would match up just like the former.

Is there something I can do? The first 5 or 6 characters should match up.

Thanks for your help!