For "a very small amount":
* Hint
* Sliver
* Whisp
* Speck
* Scantling
* Smidgen
* Dash
* Pinch
* Tinge
For "a mark or sign left behind":
* Mark
* Impression
* Footprint
* Clue
* Vestige
* Remnant
* Evidence
For "to follow a path":
* Track
* Follow
* Pursuing
* Chart
* Monitor
For "to draw a line":
* Sketch
* Outline
* Draw
* Depict
For "to find something":
* Locate
* Discover
* Detect
* Uncover
To give you the most accurate alternative, please provide the sentence you are trying to rewrite!