I look after my database and I see Wait time very high

Hello gurus,

      I look after my database on my server of production and I see :

That I have very high time / transaction for db file sequentiel read(21.43s)/txn and db file scatterred read (60.88s)/txn.

SQL*Net message to client	766,665		0	0	52.82
direct path read temp	268,523		0	0	18.50

SQL*Net message from client

769,543

164,768

214

53.02

1 - what do you think ?

2 - How can I improve ? ( Reorganize my tables of my schema ) maybe change my type of statistics.

Thank you for your advices ?

best regards

JP

Event	Waits	%Time -outs	Total Wait Time (s)	Avg wait (ms)	Waits /txn
db file sequential read	311,023		354	1	21.43
db file scattered read