I analysed an extract of the fungal mycelia by Using GC-Mass which revealed number of the compounds in which Cyclohexasiloxane, dodecamethyl, Cycloheptasiloxane, tetradecamethyl, Cyclooctasiloxane, hexadecamethyl, and 1,5-Diphenyl-2H-1,2,4- triazoline-3-thione appeared with their molecular weight, chemical formula, and chemical structure compared with its library but three compounds appeared as Cpd 4, Cpd 5, and Cpd 8 in which the GC-Mass reveled their the retention times only which are 18.99, 19.357, and 22.493, respectively as well as given their hits ( DB) which are zero (0).

Question: Why GC-Mass cannot appear the Cpd 4, Cpd 5, and Cpd 8 by their chemical structure and formula. In the precise words, are the mentioned compounds represent the new ( novel) compounds in which the GC-Mass cannot compare them with its library?.

Please, could you read PDF of the attached GC-Mass analysis?