覗う[ukagau] to peep (through)
覗き[nozoki] peeping
覗き見[nozokimi] peeking
覗きこむ[nozokikomu] to look into
覗く[nozoku] to peek (though a keyhole, gap, etc.)

覗魔[nozokima] peeping tom
管の穴から天を覗く[kudanoanakaratenwonozoku] Have a narrow view of things
覗眼鏡[nozokimegane] peep show
覗機関[nozokikarakuri] peep show
差覗く[sashinozoku] to peek

のめり込む[nomerikomu] to be completely absorbed in
圧し込む[heshikomu] to push into
意気込む[ikigomu] to be enthusiastic about
引込む[hikikomu] to draw in
引摺り込む[hikizurikomu] to drag in

引っ込み[hikkomi] retreat
引込思案[hikkomijian] reserved
引っ込む[hikkomu] to draw back
引っ込める[hikkomeru] to draw in
運び込む[hakobikomu] to carry in