I don't have a perfect answer... But I'll try to explain it the best way I can..
Speaking against The Holy Spirit , blasphemy against The Holy Spirit, is not simply saying something like "curse The Holy Spirit", it is actually knowingly, intentionally, wilfully waging war against God.
This would only occur in a specific context, for example =
"For in the case of those who have once been enlightened and have tasted of the heavenly gift and have been made partakers of the Holy Spirit, and have tasted the good word of God and the powers of the age to come, and then have fallen away, it is impossible to renew them again to repentance, since they again crucify to themselves the Son of God and put Him to open shame."
Hebrews 6:4-6 NASB
Blasphemy of The Holy Spirit is the ultimate, final, irreversible wilful rejection of the love, goodness, mercy, and grace of God in the face of Jesus Christ.
I am happy to see your interested in the Bible, ugly.