I think "보내다(送-送信,送礼物,送媚眼.....)" is more general than "부치다(寄-寄信)" in terms of meaning.
"부치다" is usually used when one sends something like a letter or package by post whereas "보내다" including the meaning of "부치다" is used to send both something real which you can see or touch like a gift, a letter, a person, etc and something abstract like "눈빛","키스","지지","힘", etc.^^
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