Can .h264 container contain audio tracks?
Your question doesn't exactly make sense. Depending on what you're asking, the answer might be yes or no.
A container for video encoded with H.264 - such as an MKV or MP4 - can absolutely contain audio. That's how you can watch an H.264 video that has sound as well.
On the other hand, it sounds like you could be confused about what H.264 actually is. H.264/MPEG-4 AVC is a standard for video compression, which has nothing to do with audio at all. The Wikipedia article on H.264 makes it pretty clear, so have a read over there if you haven't already.
I'm guessing you are using ‘.h264’ as a file extension to denote raw H.264 (AVC) video streams. In this case no, it's only a single video stream that can't include any other media streams inside it.
It wouldn't be much use on its own since a raw (demultiplexed) video stream can't be seeked (no index) and almost nothing will play it. You'd have to multiplex it together with any audio or other additional media streams into a container file (typically MP4 or MKV).
It's not common to store raw video streams without a container as standalone files. Typically they are used as an intermediate step when processing demultiplexed video and audio streams separately and deleted after use.
(The other possibility is it's just a badly-named AVC-in-MP4-container file, in which case yes you can put audio in it, but you should also rename it .mp4 to fix the confusion.)