Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
cau tren » cu tren, dau tren, ca tren
hanh dai » hanh tai, hanh dao, vanh dai
dang xay » dang van, van xay
dai cau » dat cau, da cau, dai hau
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
ve nham » ve nha, ve cham
hieu ve » hieu va, hieu van
su sach » so sach, vu sach
lang xa » lang van
lang ha » long ha
sach o » sach lo, sac o, sach y

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach o ((((lang xa) OR (dang xay))) or (lang ha)) hoi. hieu ve nham thuc va hanh dai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach o ((((lang xa) OR (dang xay))) OR (lang ha)) hoi. hieu ve nham thuc va hanh dai cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach o ((((lang xa) OR (dang xay))) or (lang ha)) hoi. hieu ve nham thuc va hanh dai cau tren".
• Adding a wildcard symbol may retrieve word variants: su sach o ((((lang xa) OR (dang xay))) or (lang ha)) hoi. hieu ve nham thuc va hanh dai cau tren*.