Namibia, Qingdao, Tanzania, most of the German Empire's countries were disbanded after their defeat in WWI. Like Germany itself did Nazi Germany want to "reunite" the German Empire and try take back the former colonies?
If this wasn't the case then why not?
The Nazis did not see a need for overseas colonies, as their focus laid on the east (I will not go into detail about those plans here).
Also, one has to keep in mind that Hitler wanted to have Britain on his side and a return to Imperial colonisation policies would have only worsened the relationship between the two countries.
There were people, usually those who were involved in Imperial colonialism, that advocated a revival, however. Paul von Lettow-Vorbeck, who fought a guerilla war in German East-Africa, for example held presentations with titles such as "Possibilities for Settlement in East Africa" in the 30's. He favoured this over Eastern Europe because it was not as developed and populated and he did not share the genocidal tendencies of the Nazis (or at least not as extreme), so the sparsely populated lands of East Africa were more suited to him.
This did not make him popular with the Nazi elites, Goebbels notes in his diary on the 21^st of January 1938:
Lettow-Vorbeck hat sich bei Vorträgen in Mecklenburg sehr mausig gemacht. Auch so ein Reaktionär! Ich werde ihm das schon versalzen.
Lettow-Vorbeck played the big shot at presentations in Mecklenburg. Another one of these reactionaries! I'll rain on his parade, all right.
And on 2^nd February
Lettow-Vorbeck stänkert gegen Staat und Partei. Ich lasse ihm das öffentliche Reden verbieten.
Lettow-Vorbeck nags against state and party. I will ban him from speaking publicly.
The problem here was that LV was too popular a figure to just silence, so he was left in peace mostly. Also the attitude towards overseas expansion changed, as an alliance with Great Britain was getting very unlikely. Still, the focus did not lie on settlement colonies (as that was still supposed to be in the East), but rather propaganda suggested that colonies would improve the public's access to consumer and edible goods.
From this point on, overseas colonies were considered, but they stood in the far future. The conquest and settlement of Eastern Europe was simply much more important to the Nazis.