Learn English – “Does the thinking correct?” and “Let we go?”

The first is correct and the best way to say it.

A simple rule when using the interrogative pronouns with a verb in a question. If the question is about the subject of the verb, you don't include do, does or did:

Who pays for that?

Who let the dogs out?

In case the question is about the object, you do include them:

Who does Santos love?

Who did the teacher punish?

Note that those examples are in simple present and simple past only. Things might change in other tenses.

Update:

Also note that You might use the second sentence if you want to use the emphatic do. The emphatic do is simple used when you want to emphasize a verb. For instance:

- I don't think you like this song.

- Come on! I really do like it a lot.

There is also the example stangdon mention below in the comments.

Both are acceptable, and understandable; however, the second is most likely the best. There are very subtle differences, though. The reason for this is in the tenses.

Sentence B is purely future tense; reaching out, letting you know, and finding are all the same tense. Therefore, one would understand that the three things are related, and are to occur in order: we'll reach out, THEN get back to you with what we find. The implication is that the finding is related to the reaching out.

Sentence A, uses a different tense for the finding. "What we have found" uses the perfect tense (usually used for something finished or completed), in contrast to the future tense of the rest of the sentence. This could be taken two ways: first, as the assumption that something definitely will be found as a result of reaching out; or second, that 'what we've found' is unrelated to the reaching out. The first would be assumed unless the context dictates otherwise.