Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
ty nang » ky nang, ty hang, ly nang
hieu ve » hieu va, hieu van
xuc van » duc van, luc van, vuc van
cua cay » cua cac
ve cam » ve cham, ve cac, va cam
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (toc sach)) ((ty nang) OR (ty xang)) co hoc. hieu ve cam xuc van hanh vi cua cay~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ((ty nang) OR (ty xang)) co hoc. hieu ve cam xuc van hanh vi cua cay*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) ((ty nang) OR (ty xang)) co hoc. hieu ve cam xuc van hanh vi cua cay*".