Have you see the Astral Development tutorials yet?
These are some popular ones but if you try the search (magnifying glass) at top right and use different search terms you’ll get a lot more ideas. It’s a common topic and this forum is 10 years old so theres a lot.
What techniques have you tried so far? Remote Influencing is heavy work and not often a one and done deal, depending on how different the new thought pattern is from older beliefs.
This tutorial is very good and a few people had results with this including me, is this like what you tried?
To find a love a basic attraction spell is the norm, as well as working on yourself: “change yourself to change your world” kind of thing.
I’m not with you, I haven’t read the books you mention tbh: so, why does a river match the intent of a love spell? Do you have to visualise a specific river in a specific way an your and your target are … swimming in it?