Perhaps you should try some spelling variations:
hoang le » hoang de, hong le, hoang lam
khoa hoi » khoan hoi, khoa hoc, khoa doi
tu sach » thu sach, su sach, te sach
ty hang » ly hang, ty xang, thi hang
hoa hoi » hoa hoc, hoa doi, hoc hoi
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, sach thu
cam tuc » cam xuc, cam tu, nam thuc
tuc ban » thuc ban, truc ban, tu ban
hang le » tang le, hang ly, hang ke
ve cam » ve cham, ve cac, va cam

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ty hang ((hoa hoi) OR (khoa hoi)). hieu ve cam tuc ban ((hang le) or (hoang le)) cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty hang ((hoa hoi) OR (khoa hoi)). hieu ve cam tuc ban ((hang le) OR (hoang le)) cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty hang ((hoa hoi) OR (khoa hoi)). hieu ve cam tuc ban ((hang le) or (hoang le)) cua vat".
• Adding a wildcard symbol may retrieve word variants: tu sach ty hang ((hoa hoi) OR (khoa hoi)). hieu ve cam tuc ban ((hang le) or (hoang le)) cua vat*.