I'm sure lots of clubs would like to buy the players you suggest, but you need to consider how many clubs actually think they have a chance of signing those players? I'm not sure if you've ever noticed it, but the vast majority of the time the AI only makes moves for the players at a human club that it could feasibly land (ie. players who wouldn't turn down the move). If you have players like Ronaldinho, firstly the AI is going to consider that you'd be unlikely to want to sell him, and if Ronaldinho is settled/happy at his current club there is a small chance that even if the AI could meet your valuation of the player that Ronaldinho would even want to discuss terms - so the AI probably judges it as a waste of time making the move - of course, the AI doesn't consider it a waste of time to continually pester you with the same derisory offer for one of your wonderkids but that's another matter
Now, if you're trying to get rid of these players because they're old and not much use to your current tactics, the advice given above is good. It is also worth bearing in mind that clubs are more likely to bid upon those players that are actively playing, so if you have a high-ranking feeder club, you should set their status as not wanted and send them off on-loan until the next transfer window, or try and arrange a five/six-month loan deal with another club. If other clubs sense a player is available AND they can see what he's capable of then they're more likely to make a bid for him.
My reserve squad had grown ridiculously huge due to my habit of signing reasonable-Bosmans as backup and potential young stars so I loaned out pretty much everyone I could and then weeded through those I didn't want at the end of the season, placing them on the transfer list etc. and lo and behold I spent most of the summer clearing out the unwanted players and lowering my reserve team to a much more reasonable size - whilst also clearing a huge chunk of my wage bill. :cool: