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
hieu van » thien van, lieu va, hieu ve
hoc sach » hoc sinh, hoc cac, hoc anh
ty nang » ky nang, ty xang, ty hang
cho hoc » co hoc, khoa hoc
hieu va » lieu va, hieu qua
cua chu » sua chua
xu van » tu van, vu van, su van
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: ((toc sach) OR (hoc sach)) ty nang cho hoc. ((hieu van) or (hieu va)) chao xu van hanh vi cua chu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) ty nang cho hoc. ((hieu van) OR (hieu va)) chao xu van hanh vi cua chu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) ty nang cho hoc. ((hieu van) or (hieu va)) chao xu van hanh vi cua chu*".