I interpret your question to be that you want to find out "what" the
string means, to the best of one's ability to interpret it.
First of all, the first three characters "sad" clearly indicate a
negative mood to the person creating the string and give a clue as to
how to interpret the rest of it.
JCH must be someone's initials, when searched for produced the name
"Juliusz Chroboczek". Immediately after JCH, is "frwn" or "frown"
again a sad context, either meaning that Juliusz Chroboczek is sad or
has somehow done you some wrong.
icowu4tu, or "I cow you for too" probably is some reference to getting
even with this person who made you frown, or perhaps is some reference
that even sad people need to eat, "I cow for you too" being a similar
reference to "a chicken in every pot".
the [ next indicates a new idea, like a period.
2xlnjpw54oro, to me looks like a product description. double extra
large new jersey pants with 54 outer radial orifice (outer radial
orifice a fancy term for waist size)
I trust this interpretation meets your needs in answering the question
of "what" in regards to the string presented.