Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
doc sach » hoc sach, nuoc sach, dac sac
luoc van » luoc can, luoc va, luc van
nang cho » nang chon, ngang cho, nang cao
nuoc dan » nuoc dang, nuoc san, duoc dan
hanh di » hanh vi, hanh de, hang di
hieu va » lieu va, hieu qua
cho hoc » co hoc, khoa hoc
ty nang » ky nang, ty xang, ty hang
cua chu » sua chua
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 (doc sach)) ty nang cho hoc. hieu va cac ((nuoc dan) or (luoc van)) hanh di cua chu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (doc sach)) ty nang cho hoc. hieu va cac ((nuoc dan) OR (luoc van)) hanh di cua chu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (doc sach)) ty nang cho hoc. hieu va cac ((nuoc dan) or (luoc van)) hanh di cua chu*".