Entry for Procurement / Namibia

Many of the government departments have a section on their website advertising tenders. However, I have not found a website that has a collection of ALL government tenders.
The links I found:
http://www.mof.gov.na/tender-advert

http://www.moe.gov.na/m_proc_procurement.php

http://www.mhss.gov.na/tenders-vacancies/
http://www.ecn.na/vacancies-and-tenders
http://www.mgecw.gov.na/vacancies-and-tenders

However none of these sites are updated / have tenders available.