translation: Update chapter_graph/index.md

[K3v123]

Just changed the words a little. honestly the Machine translation is good already.

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[K3v123]

I'm considering whether "vast" might be more appropriate, you can find an example in The Times stating, "They can search the vast database by age, by ability, by certain strengths." I think "database" aligns well with "network graph" in this context. It shows the extensive scope of the database, suggesting that "vast" aptly conveys the breadth and depth of the available resources.

Hi pengchzn thanks for your comment! your right vast does make it a bit better. I'll change it back now.