Sorry, read your dictionaries
before posting, Tung Quoc. This is
a good one. A better one is the its unabridged version, for isn't free
though, but not too expensive .
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newly
1 : LATELY, RECENTLY <a
newly married couple> <
newly affluent>
2 : ANEW, AFRESH <
newly painted> <jurors
newly selected for each case>
http://www.m-w.com/dictionary/newly
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clearly shows that beside "recently," "newly" has other meanings, and those meanings are presented there.
Thus, they are interchangeable only in meaning 1, and you should be
careful, as "newly" carries meaning 2 with it too, and people reading
your sentences must be able to know what was your intention.