How would a Catholic explain the absence of the mass in the Epistle to the Hebrews?

I noticed Hebrews is really the place where the Priesthood is discussed as how the priestly ceremonies are related to the Christian faith. It seem rather complete and in depth. Hebrews says a whole lot about the priesthood and even goes into ‘great depth’ explaining things ‘difficult to understand’. It covers many great mysteries fulfilled in Christ through the priesthood. As far as I know, Catholics view the mass as kind of mystical repetition of the sacrifice of Christ. Not that Christ is sacrificed again but that his one and only past sacrifice is somehow 'redone' by himself in an unexplainable way. Catholic priests officiate in the mass so that Christ, as the high priest ‘sacrifices himself’ in the present tense. This is done in order to further sanctify those who partake of the ceremony. If this were true, I can’t fathom why the author of the Hebrews would not somewhere indicate recognition of the existence of this practice. Would he not link it into his teaching of the priesthood and the high priest? **If believers were regularly partaking in a ‘mass’ with an understanding that Christ was sacrificed over and over, why does the Epistle to the Hebrews not seem to be aware of such an important aspect of the priesthood while it explains the meaning of the priesthood?**