Mantenkun drills (help)

The publisher is not "Land" computer, but "R&D" computer, see the texts on those manuals. It might be related to http://www.generation-msx.nl/msxdb/softwareinfo/650 but I'm not sure.

So, at least the end of the name is about '10 volumes'. Google says: 10 volumes thorough drill marks kun. It's an educational program which helps to drill for school...

mmmh, yes, at a first sight I created R&D Computer, but after that I saw this was already in the database as a Land Computer release. So I though R&D Computer was like a serie (for ex.Research & Development). Tagoo says this: http://msx.jpn.org/tagoo/s_check.cgi?LINE=330

The phonetics say "Randokonpyutaa", but the "R&D Computer" is pretty clear... So I think they used weird phonetics... Note that R&D written in full is R AND D - "RAND" and Japanese has no distinction betweeen R and L. So I really think it's the same.