Why is 我找不到 correct and 我不能找 wrong? Which grammatical point am I missing? I was recently corrected by a Chinese friend. He said it's incorrect to say:


  我不能找


He said the right form is:


  我找不到 


Which sentence structure pattern is this following. Is it used with only certain verbs? Only with 能／可以／会？

Thanks!
In general,

"我不能找"： 


  I'm not able/ allowed/ permitted/ qualified to look for
  something/somebody.


"我找不到"： 


  I am not able to/ cannot find the things that I am looking for.


Typically, native speaker seldom use "我不能找".

English speakers don't quite say "I cannot look for something" either, right?