Getting out of mid range score

<p>Is there a way to get out of 650- 700 range in writing? I have taken so many tests but writing score never improved… I think I know all the rules and I usually finish within 18 mins but I still get stuck in that range…</p>

<p>Is there a way to get out?</p>

<p>Also, do u know any good methods to improve In idiomatic questions?</p>