...สิ่งที่พระพุทธเจ้าตรัสรู้ คือ อริยสัจ 4 นั้น เรียกว่า “ธรรม” ซึ่งเป็นคำที่มีใช้อยู่ก่อนการตรัสรู้แล้ว...
I would rewrite this --very carefully--.
What the Buddha discovered is not "ariya sacca".
"Ariya sacca" is as has been "the way of Ariyan" (a race of people which the Buddha was born into). This principle of analysis seems to have been practiced long before the Buddha time.
Please, search the Net and read about ปฏิจจสมุปบาท or 'what the Buddha discovered' to see the foundation of Buddhist concepts is about "factors and effects" (the webs of relations [over time and space] or the law of Kamma). It is agreed that the word 'Dhamma' was in use well before the Buddha time, and there are many 'meanings' for dhamma. 'Ariya sacca' (when 'religiously' practiced/used) is "a" dhamma in one meaning. The late venerable Buddhadaasa had offerred many more meanings: "duty", "way things are", "cleaning" (home and mind),...
We should help to clear the "way of the Buddha" from misconceptions and half-truth (half avijja).