Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
van hanh » van thanh, ban hanh, van anh
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
xuc van » duc van, luc van, xuc ban
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
ve cam » ve cham, ve cac, ve cai
va cam » va cham, va cac, va cao
ma hoi » mai hoi, xa hoi, ma hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang ma hoi. hieu ((ve cam) or (va cam)) xuc van hanh vi ((cua tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ma hoi. hieu ((ve cam) OR (va cam)) xuc van hanh vi ((cua tre) OR (cau tren)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ma hoi. hieu ((ve cam) or (va cam)) xuc van hanh vi ((cua tre) or (cau tren))*.