If i remember correctly, it says in the description that their longbows were made from bamboo and from what i've seen with bamboo (and tried a few times) they arent as good as woods such as yew or ash or composite materials in making bows.

I think that the reason they had a long bamboo bow was that because bamboo wasn't as great as other bow making woods and so a bamboo long bow would prob. (IMO) have around the same strength (and therefore stats) as a regularly sized wooden bow in the west.

That would justify its lack of range and lack of stopping power when one thinks of a longbow.

*and BTW, the longbow worked because it killed the horses of the knights, and since their armor was so heavy, it was quite hard to close in that bit of distance while under constant fire and if they did manage to get close enough on foot, they would be substantially more exhausted than the archers who can then dispatch them with nice armor piercing stilettos.

^^ (sounds familiarly similar to them indian archers?)