Perhaps you should try some spelling variations:
sach tham » sach nha
sach thu » sach thue, sach thieu, cach thuc
nang cho » nang chon, ngang cho, nang cao
cho hoc » co hoc, khoa hoc
hieu va » lieu va, hieu qua
luc van » luoc van, duc van, luc va
luu van » cuu van, luan van, luu hanh
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 thu) or (sach tham)) nang cho hoc. hieu va cac ((luc van) OR (luu van)) hanh vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach thu) OR (sach tham)) nang cho hoc. hieu va cac ((luc van) OR (luu van)) hanh vi cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach thu) or (sach tham)) nang cho hoc. hieu va cac ((luc van) OR (luu van)) hanh vi cua cau*".