Those sound like questions on the Calif part-year/nonresident Schedule D Worksheet and are a little difficult to understand. I'll try to unravel them:
Gain/loss from Calif sources as if a nonresident for full year - this is as if you lived in, say Vermont, all year and you sold real estate located in Calif. Enter the gain or loss on dispositions like that (property is in Calif).
Gain/loss during the portion of the year you were a Calif resident - If you were a Calif resident during any of 2017 enter all gains/losses earned during that time - it doesn't matter where the property is. If never a Calif resident in 2017, skip it (if it wants an entry, enter 0).
Earned from CA source while a CA nonresident - this is the opposite of the one just above: Enter all gains/losses from Calif sources (i.e. real estate located there) during the time you didn't live in Calif. If you were a full-year nonresident then this is the same number as the first question above.
