探索, 系统 tan4suo3, xi4tong3 explore, system.

探索 tan4suo3　quest explore probe

探hand groping about in a cave for structured patterned substance tan4 探
explore, search, scout visit

索suo3 search, rope, cable.

索 great master on top; small silk below = man with rope, pulling it as idea of SEARCHING, REQUESTING

系统　xi4tong3 system
bind+tie all together
Research.

系　line on top means bound silk in the middle small on the bottom = small silk thread is BOUND, BIND

统　tong = all tied together

xitong = system