Perhaps you should try some spelling variations:
sach pham » sach tham, sach phat, sach phap
hau truc » cau truc, hang truc, hoc truc
thang va » trang va, thong va, thanh va
truc vat » thuc vat, truc va, truc van
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
danh vi » dinh vi, danh di, danh va
van hau » van ha, van hai, van dau
cuu tre » cua tre, cau tren, cau treo

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 pham ((thang va) or (hang va)) hoi. hieu van hau truc vat ((danh vi) or (hanh vi)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach pham ((thang va) OR (hang va)) hoi. hieu van hau truc vat ((danh vi) OR (hanh vi)) cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu sach pham ((thang va) or (hang va)) hoi. hieu van hau truc vat ((danh vi) or (hanh vi)) cuu tre*.