This paper is not smooth enough.

这纸不太光。

《新英汉大辞典》

The way of true love is not smooth.

真实爱情的途径并不平坦。

youdao

The path of true love is not smooth.

真正的爱情之路是不会平坦的。

youdao

Warhol used a very smooth painting method so the artwork almost did not look hand-made.

VOA: special.2010.09.05

Fred Barnes, editor of The Weekly Standard magazine "Obama,while a glib and smooth speaker, is not particularly persuasive,"

VOA: standard.2009.09.02

It is not normal to have just a smooth, easy ride through a World Cup qualifying.

VOA: standard.2009.06.07

Be sure your business card is plain on the back and not smooth to allow you to write on it.

FORBES: Create a Healthy and Prosperous Business

Both of these fossils suggest such transitions are not smooth, simultaneous transformations of all bodily features from old to new.

ECONOMIST: How new groups of creatures emerge

As I understand it, the DSG or "dual-clutch" transmissions on VWs, while not smooth as silk in their operation, are mechanically solid.

WSJ: Me & My Car: What's the Best Tire Pressure for a Saab?