Theft in airlines

I flew fro OR Tambo to Cape Town Airport today 8th September @ 9:30 flight number FA292, my jewellery was ****** in my check in bag, I call the airline they say there is nothing they can do as they handle the bag, they are handled by independent bag handling Co that why they don't advise to put valuable in check in bag, I get that, I understand the part of valuable items story, but why was my bag tempered with in the 1st..for me it's not the issue of protecting my valuables by not putting them in the checking in bag, it's an issue of security. If they opened found no valuable and what is valuable because everything that in my bag is valuable and private, it is also an issue of security what if the put illigal stuff my bag and get arrested for something that don't know.. i found my toiletry & make up bags open and my stuff all over, while they were searching left my coconut oil open spilled all over my clothes ????????????????????????????????????????????