Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hang cho » sang cho, hang khoa, phong cho
hanh vai » hanh vi, hanh va, hanh tai
van hanh » van thanh, ban hanh, van anh
cac vuc » cac nuoc, cac vung, cac cuoc
cua cau » cua cac, cua chu, cua can
vuc van » duc van, luc van, thuc van
hieu va » lieu va, hieu qua
sach ty » sach y, sach tu, sach thu
hieu ve » hieu van
cho hoc » co hoc, khoa hoc
ty hang » ly hang, ty xang, thi hang
cua cay » cua 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 ty hang cho hoc. ((hieu ve) or (hieu va)) cac vuc van hanh vai ((cua cau) OR (cua cay))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty hang cho hoc. ((hieu ve) OR (hieu va)) cac vuc van hanh vai ((cua cau) OR (cua cay))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty hang cho hoc. ((hieu ve) or (hieu va)) cac vuc van hanh vai ((cua cau) OR (cua cay))*".