“如此” is usually used with “原来” as a combination.
EX: A: I lived in Korea for many years so I can speak Korean fluently.
B: “原来如此” / No wonder.
“如此” can also be used to emphasis your expressions.
EX: 今天的天气如此晴朗! / What a sunny day today!
“这样” has almost the same meaning as “原来如此”.
EX: A: I lived in Korea for many years so I can speak Korean fluently.
B: “这样啊” / No wonder.
“这样” also means "well".
EX: 我今天没有空。这样吧,我们明天早上见面怎么样? / I'm not available today. Well, how / what about tomorrow morning we meet each other?
I hope that woule be helpful to you.
Zhao Lei