Perhaps you should try some spelling variations:
doc sach » hoc sach, nuoc sach, dac sac
toc sach » hoc sach, thuoc sach, nuoc sach
van hanh » van thanh, ban hanh, van ban
nang cho » nang chon, ngang cho, nang cao
van anh » van thanh, tuan anh, van minh
hieu ve » hieu va, hieu van
cho hoc » co hoc, khoa hoc
ty nang » ky nang, ty xang, ty hang
cua cau » cua cac, cua chu, cua cay
ve cam » ve cham, ve cac, va cam
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: ((doc sach) OR (toc sach)) ty nang cho hoc. hieu ve cam xuc ((van hanh) or (van anh)) di cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doc sach) OR (toc sach)) ty nang cho hoc. hieu ve cam xuc ((van hanh) OR (van anh)) di cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc sach) OR (toc sach)) ty nang cho hoc. hieu ve cam xuc ((van hanh) or (van anh)) di cua cau*".