Searchable combo-box in user-form

The relationship is like this
Attachment 747605

The txtTube list will be depend on txtMachine
example: txtMachine is Diffusion, and on the txtTube it will show all the Diffusion Machine
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What i'm trying to achieve here is to do a searchable combobox inside txtProblem which depend on the txtMachine
The data for txtProblem is under "Diffprob,Aldprob,printprob etc"

example1: txtMachine is Diffusion, then under txtproblem it will show "diffprob data" and as we type in the combobox (txtproblem) it will do a searchable just like google search suggestion (diffprob data)

example2: txtMachine is Sela, then under txtproblem it will show "aldprob data" and as we type in the combobox (txtproblem) it will do a searchable just like google search suggestion (aldprob data)

i hope i make it clear

Below is an example of searchable combobox that i would like to do
The combobox will dropdown some suggestion as we type