Hi Muhammad
Your link building and SEO strategies to a large extent should be no different than before Hummingbird. To qualify that I would say that is true if before Hummingbird you were already creating content that focussed on answering the needs of people for questions they were asking and information they were looking for.
I would recommend you read a recent blog post on Moz by Gianluca Fiorelli about Hummingbird entitled "Hummingbird Unleashed" in which Gianluca very much explains what has changed and what those concerned with marketing online should be doing about it. For me the quote I found to be very helpful was "We should stop focusing only on keyword optimization and start thinking about topical optimization" and that I think at the heart of the Hummingbird update.
With regard to link building, your strategy (which hopefully it was before) should be to make sure that links are built from other sites and pages that are relevant to the topic of your site and pages. Gone are the days when any backlink was good and the more inbound links you could build the better. A lot of site's ranked well using that strategy, but one by one those sites are falling by the wayside.
So set a foundation to build topical content that people want to read and share and you will be heading in the right direction.
I hope that helps,
Peter