Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
doanh van » doan van, doanh va, doanh ban
thuc dan » thuc hanh, hoc dan, thuc vat
ty trang » ta trang, te trang, tu trang
trang xa » trang va, trang ha, trong xa
danh vai » danh sai, danh va, dang van
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
hieu ve » hieu van
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: su sach ty trang xa hoi. ((hieu ve) OR (hieu va)) nham thuc dan ((danh vai) or (doanh van)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty trang xa hoi. ((hieu ve) OR (hieu va)) nham thuc dan ((danh vai) OR (doanh van)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty trang xa hoi. ((hieu ve) OR (hieu va)) nham thuc dan ((danh vai) or (doanh van)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: su sach ty trang xa hoi. ((hieu ve) OR (hieu va)) nham thuc dan ((danh vai) or (doanh van)) cuu tre*.