Confusion regarding the use of ‘threw’ and ‘through’ arises from the fact that they are homophones, ie, they are pronounced the same way. As a result, it is quite possible for one to be mistakenly used in place of the other. However, there is no similarity in their meanings:
‘Threw’ is the simple past tense of ‘throw’, when the latter is used as a verb.
meaning(s): to hurl or cast something from the hand or to project one’s voice. He threw the ball at the stumps, looking to run the batsman out.
‘Through’ is generally used as a preposition. Meaning, in brief:
to get into something from one end or side and come out the other. Example - The sunlight coming through the window woke me up.
to travel over or across or in something. Example - The plane hurtled through the air at supersonic speed.
to go past or beyond something. Example -The fugitives went through three red lights before the cops finally caught up with them.
to go from one to another of, or between or among individual members of something. Example -Tarzan swung through the trees like the forest was his natural habitat; The World Cup may have passed through many hands, but it is now India’s.