Facing TV Problems? Ask a TV Technician.
I don't know what you mean by 'the cover... that hold the compotes'... I guess you mean the main cover of the TV, over the internal electronics generally.
It may have pressure snaps. But I honestly do not know. In general, when a device has a cover where 'all the screws have been removed but the cover won't come off', then either not all the screws are off - e.g. there's some screws under caps or other little screw-covers that are loosely glued on and come off - or else something else has to be removed first, that the retaining screws are underneath.
As for specifics for this device model... There is little to point to. Perhaps this:
might lead to your obtaining a service manual. Which usually has diagrams or instructions that help with disassembly.
Are you experienced at all with electronics repair or troubleshooting?
Do you own an electronic volt meter?
How old is the TV, please? measured from its date of purchase.