I don’t know what parts Seeed uses, but I have used the following, available from Newark and made by Multicomp:
Female Crimp Pins: 2226TG
Receptacles: 2226A-02 (single row, two positions; replace the “02” with the number of positions you want, and replace “A” with “B” if you want dual row)
Crimping Tool: HT-225D (somewhat expensive but makes building jumpers so much easier)
I didn’t find any male crimp pins at Newark, but maybe I just didn’t look hard enough. Hoping they were somewhat standardized, I took a chance with some from Pololu. They worked just fine with the Multicomp receptacles and crimp tool, despite probably being made by a different manufacturer. They also sell female pins, receptacles, and crimping tools.
Knowing what to search for is half the battle. Now that you know what these parts are called, you may be able to find them through other suppliers as well.
Hope this helps!