Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach thi » sach thu, sach tai, sach thieu
hieu van » hieu va, thien van, lieu va
nang cho » nang chon, ngang cho, nang cao
thi nang » thi cong, ki nang, thi hanh
cho hoc » co hoc, khoa hoc
hieu ve » hieu va
cac xuc » cac nuoc, chat xuc, cac cuoc
van anh » van thanh, tuan anh, van minh
cua cay » cua cac
anh vi » hanh vi, anh va, anh ve
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 thi nang cho hoc. ((hieu ve) or (hieu van)) ((cac xuc) OR (cam xuc)) van anh vi cua cay~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach thi nang cho hoc. ((hieu ve) OR (hieu van)) ((cac xuc) OR (cam xuc)) van anh vi cua cay*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach thi nang cho hoc. ((hieu ve) or (hieu van)) ((cac xuc) OR (cam xuc)) van anh vi cua cay*".