Perhaps you should try some spelling variations:
parallel tutorial » parallel bacterial, parallel serial
function function » function functional, functions functional, function dysfunction
function https » functions https, fiction https
tutorial plc » tutorial vls, tutorial c, tutorial ql
plc function » c function, ic function, fec function

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: parallel tutorial plc function function https~.
• Adding a wildcard symbol may retrieve word variants: parallel tutorial plc function function https*.