Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thi nang » thi cong, ki nang, thi hanh
nuoc san » nuoc luan, nguoi san, nuoc quan
luoc can » luc canh, hoc can, luoc dai
cua cay » cua cac
hieu ve » hieu va, hieu van
cao hoc » co hoc, cho hoc, chat hoc
vi cua » vai cua, di cua
ve cac » va cac, vien cac

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)) thi nang cao hoc. hieu ve cac ((luoc can) or (nuoc san)) hanh vi cua cay~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) thi nang cao hoc. hieu ve cac ((luoc can) OR (nuoc san)) hanh vi cua cay*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) thi nang cao hoc. hieu ve cac ((luoc can) or (nuoc san)) hanh vi cua cay*".