It's possible. Basically, it's similar to other mind thingy. It's all about vibration and signal. The problem isn't about how to make your thought available for other people. The problem is the receiver. Some people aren't sensitive enough to 'catch' those vibrations (signal or whatever you call it) to gain the 'information'.
For example, when you were playing with your childhood friend, you could share the idea of those castle and dragon while playing. "Look! A dragon! Let's slay it!". You and your friends could 'see' the dragon right? I bet you could. This is because children are more sensitive about human mind than most adults. Children can feel others feeling better than most adults. They're more sensitive, so they can catch informations from other's mind by their 'vibration'.
In more intense practice, this martial art. We train to contact spirits. The training is held in a local graveyard during the night. Creepy? Yes. Some disciples can't 'feel' the existence of the spirits, while some other can. That means they're not sensitive enough, and they're not focused enough. The 'image' of the spirit caught by these focused disciples is the same. If one meets a spirit of an old lady, other who meet her will say the same about the lady's experience.
The point is to radiate the signal of your thing (tulpa, information, message, etc) and the receiver tries to catch it. If the receiver isn't sensitive enough, the receiver may miss it. That doesn't mean it's all the receiver's fault. The sender need to radiate it correctly and as clear (strong) as possible.
Let's say it like this : the sender 'speaks' and the receiver 'listens'. If the receiver is deaf, the information spoken by the sender can't be caught by the receiver. If the sender speaks too quiet, the receiver can't hear it. If the sender speaks with foreign language or unclear accent, the receiver may not understand the spoken information.
It's all about communication. Remember than brain vibrates and you can feel the signal. If you focus on thinking about something, the vibration about that thing will be stronger. Therefore, it's easier to read.
Other examples are : mind reading, "I know that feel" thingy, I feel like my son is in trouble, I think she's sick, I feel like he has a problem, "LOOK! A dragon!", I feel like someone is sneaking behind me.
Well, you can believe me or not. For "spiritual masters" like you guys, an idea from a 'newbie' like me may be so 'meh', so I will just leave it here for consideration.