Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach thi » sach thu, sach tai, sach thieu
thi nang » thi cong, ki nang, thi hanh
nang cho » nang chon, ngang cho, nang cao
cho hoc » co hoc, khoa hoc
van cac » van hac, van cau, dan cac
van bac » van ban, van bao, van hac
duc van » duc va, duc manh, duc phan
cua cau » cua cac, cua chu, cua cay
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 ((van cac) OR (van bac)) ((duc van) or (duc tan)) hanh vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach thi nang cho hoc. hieu ((van cac) OR (van bac)) ((duc van) OR (duc tan)) hanh vi cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach thi nang cho hoc. hieu ((van cac) OR (van bac)) ((duc van) or (duc tan)) hanh vi cua cau*".