Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
nang cho » nang chon, ngang cho, nang cao
van hanh » van thanh, ban hanh, van anh
hoc sach » hoc sinh, hoc cac, hoc anh
tu nang » tru nang, tu nong, tu nano
cho hoc » co hoc, khoa hoc
van cac » van hac, van bac, dan cac
van cau » van dau, van hau, van chat
xuc van » duc van, luc van, vuc van
hanh di » hanh vi, hanh de, hang di
cua cay » cua cac
di cua » dai cua, doi cua, de cua

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

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