Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
doc sach » hoc sach, nuoc sach, dac sac
van hanh » van thanh, ban hanh, van anh
nang cho » nang chon, ngang cho, nang cao
cua cau » cua cac, cua cay, cua can
duc van » duc va, duc tan, duc manh
cac duc » cac du, cao duc, cac dac
hieu ve » hieu va, hieu van
cho hoc » co hoc, khoa hoc
ty nang » ky nang, ty xang, ty hang
cua chu » sua chua
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: ((toc sach) OR (doc sach)) ty nang cho hoc. hieu ve cac duc van hanh vi ((cua cau) or (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 ve cac duc van hanh vi ((cua cau) OR (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 ve cac duc van hanh vi ((cua cau) or (cua chu))*".