During his hunt, Kang had a lot of things going through his mind, the most important being his absorbed abilities. Some were becoming useless and unneeded and he was quite aware he had to get rid of some to free space for the space-related abilities.
Although he knew the space abilities wouldn't work right away because he had no mana, he just wanted to have them so the heavenly demon could answer his inquiry and provide the rift solution.
Finally, Kang found himself in a tough situation considering what he should keep and what he should get rid of. After a while of thinking, Kang decided to get rid of the ones he used the least and the ones that didn't benefit him much compared to before.