Improve the level of vs Raise the level of

Some examples from the web:

• It contributes to improve the level of absorption of other slowly
• digested supplements.
• The EDPS has made several proposals to improve the level of protection.
• The overall aim of harmonising the classification and labelling of hazardous chemicals is to improve the level of protection of human health and the environment throughout the world.
• improve the level of knowledge of voluntary activities within their national territories and transfer this information to the European Commission for further dissemination;
• An environment embracing 'safety culture' principles should not prevent action being taken where necessary to maintain or improve the level of aviation safety.
• fighting them helps to improve the level of public health and to boost food safety in the Union.
• In order to incentivise undertakings to improve the level of environmental protection beyond these mandatory Union standards, State aid in this area should be covered by the block exemption.

Some examples from the web:

• That will help us raise the level of mutual understanding and interconnection.
• Firstly, I would like to focus on consumer empowerment and I would like to highlight the need to raise the level of financial literacy.
• Establishing an International Day of the Heroes of the Fight Against Totalitarianism would undoubtedly help raise the level of knowledge about a painful past.
• In the course of the debate is emerged the necessity to raise the level of political attention on the port in order to shorten this tempistica.
• This demonstrates that there is much to do in order to raise the level of trust among the Member States.
• The same objective to raise the level of qualification of the young people with Bac or Bac+2 would have to rest on an organization of the common formation between school and companies, as in Germany or in the Scandinavian countries.
• We must be aware that the EU's commitment to raise the level of emission reductions by 30% by 2020 is conditional on comparable or proportional commitments being assumed by third countries.
• Strategic Plan of Implementation (2013) to raise the level of integration and objectives in the three sectors of H2020.