## Answer based on the text ##

There's no motive given or hinted at in the text or elsewhere, so I'm afraid the only answer I can perceive is 'no' - there is no way to explain Terach's attempt to travel to Canaan based on the text.

## Other Thoughts ##

As pointed out by Abu in the comments to his answer, Canaan was the heart of the 'fertile crescent' linking Eurasia with Africa, and so it's a very natural trading link. For somebody such as Terach who was relocating for any number of reasons, Canaan would be one of the most natural directions to move - it wasn't a known region to their family, but it was still a highly 'significant' area for the ancient world. It's no co-incidence that when Abram moves there he encounters ten or more kings already settled in the region (Genesis 14).