My deck has begun to separate from house (see pics). Look for help on how to move it back and secure to house.
In all honesty, you are kind of chasing after a chimera trying to do something like that.
The likelihood is that the footings for the deck are inadequate, so that is why it is shifting. Trying to attach it to the house is not a solution. If the foundation of something is unsound, then that thing is unsound. A lot of people think they can just build decks on mud, then when bad things happen they start trying crazy stuff. Look, if the foundation of your deck is shallow, then that is your problem.
Here is the solution to your problem: build proper footings for your deck.
Decks in seismic zones are now required to be tied to the main house with “tension ties”.
It will be difficult to move the deck back into position without house jacks. Here’s a tension tie that you could use to help “move” you deck back into position:
Attach a new treated 2x10 or deeper deck ledger to the existing deck ledger to make sure that your deck won't just fall off. Then use a lot (up to 1 per joist) of Simpson DTT1Z deck tension ties to suck the deck back to the house. Tighten each one 1/8" at a time and slowly walk it in.
The DTT2Z requires you to put threaded rod through the brick and into the floor system of your living space, so it's a solution but only a good one for new construction to meet code.
Step 1 - contact local zoning board
Step 2 - follow instructions of local zoning board.
If local zoning board doesn't exist contact local engineering firm, the deck and house should have been tied together unless you're in an earthquake prone location.
The pictures aren't visible to me and without then I'm shooting blindly in the dark here but it's possible the deck wasn't properly engineered or properly installed. If the concrete footers weren't properly installed then frost heaving could be moving them...
People are killed every year by improperly engineered and improperly installed decking, consult an expert and not the intrewebs because the life you save could be your own.