The difference between ranlov and seqlov is that for randlov, the values from your seedlist are picked in a random order while for seqlov it will be picked sequentially.
Eg: For Seed Values - 1,2,3,4
Randlov might use the values in random order say 2,4,3,1 and this may change with each run but seqlov will always use values in 1,2,3,4 order.
You can refer the below link to get details of all functions available with detailed explanation.
Data Generation Functions and Parameters - CA Test Data Manager - 4.5 - CA Technologies Documentation