Can’t Find Stud Joists To Fix Flat Tv Bracke To – Tried Stud Detectors

Hi I am trying to fix a 32″ flat screen tv to a wall I assumed was hollow and had stud joists. I live in uk and all the internal walls are hollow and a pain to work with ie have to use special hollow rawlplugs etc. I bought a bracket to fix the tv onto, instructions say it must be fixed to stud partitions if a hollow wall, so now have tried two makes of stud detectors, they just bleep all over the place and randomly, ie I cannot locate vertical studs at all, cannot understand, this is a wall that separates my house from another, although it sounds hollow, could it be that in fact it is solid underneath, and that is why I can’t locate joists? Because it sounds very hollow, perhaps this is plasterboard for cosmetic reasons which is not affixed to brick wall? What do I do as I do not want tv collapsing or ruining a wall I will not get back perfect again even if I fill it etc? thanks for help

Where Can I Buy The Cheapest Flat Screen Tv`s .i Live In The Uk And Ive Tried Ebay?

Im looking to buy online so anywhere in the world as long as there inexpensive and good quality.