improve on

He is looking to improve on his admittedly modest achievements so far.

迄今为止，他确不算大，他打算更进一步。

Knotless operation can reduce yarn defects and improve resultant yarn quality on a certain degree.

无接头操作法在一定程度上减低了纱疵,对纱质量有很好改善。

At the same time, to levy enough in time and operate macro-economic control well, levier should plan tax by improving on tax laws and enhancing the management of tax.

同样，主体为了依法尽可能及时足和发挥好宏观经济调控职能，也需要通过完善法和加强等途径进行筹划。