Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
thuc dan » thuc hanh, hoc dan, thuc vat
thuc day » thuc vat
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu van
hieu va » lieu va, hieu qua
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang
cua te » cua tu

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 v nang ma hoa. ((hieu ve) or (hieu va)) cau ((thuc day) or (thuc dan)) hanh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach v nang ma hoa. ((hieu ve) OR (hieu va)) cau ((thuc day) OR (thuc dan)) hanh vai cua te.
• Adding a wildcard symbol may retrieve word variants: tu sach v nang ma hoa. ((hieu ve) or (hieu va)) cau ((thuc day) or (thuc dan)) hanh vai cua te*.