Please explain these lines (or what wind serves to advance an honest mind)
This is just a metaphor suggesting that honesty is not the best policy for getting ahead in the world. The image is that of a sailing vessel catching a wind that will move it in the desired direction. The words "wind" and "mind" are what I believe are called rimes a l'oeil (rhymes to the eye): they don't rhyme but look as if they should. I believe the lines should be: "And find / What wind / Serves to advance an honest mind." Donne is just itemizing things impossible to do, ending with the main thought that it is nearly impossible to find a woman who is both fair and faithful. The poem is sometimes titled "Goe, and Catche a Falling Starre."
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