I would say that "I can't see it anywhere." and "I can't find it anywhere." can have the same meaning but "I can't see it anywhere." implies that you are actively looking whereas "I can't find it anywhere." could be used to inform someone of your search but you aren't necessarily actually searching for it at the time. "I am writing to..." indicates the writing is in progress. "I write to..." doesn't imply immediacy. In the last sentence, "sneaked" is the acceptable past participle of the verb but I would change the phrase to: "...the thief had sneaked into tmy house." "Into" is much more common. Also, it is acceptable (although there is a debate concerning this, to use "snuck" for sneaked. Several dictionary sources accept "snuck" in place of "sneaked", especially in the last 20 years.

真有意思。

Thank you very much, Max P!

http://www.merriam-webster.com/words-at-play/snuck-or-sneaked-which-is-correct ‘I write to’ is a very, very direct way of saying it. It's not wrong to say that you write to someone, but it is not how people talk. Yes ‘I can’t see it anywhere’ same thing.