Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, thai thuc
doanh van » doan van, doanh va, doanh ban
tam thuc » am thuc, nam thuc, dam thuc
danh vai » danh sai, danh va, dang van
su sach » so sach, vu sach
cuu tre » cua tre, cau tren, cau treo
sach xa » sach dao, sach nha, sach bai
hieu ve » hieu va, hieu van
tang ha » lang ha, tang ma, trung ha
xa tang » ha tang, ca tang, ba tang
ha hoi » hoa hoi, ha noi, xa hoi

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 xa tang ha hoi. hieu ve ((tham thuc) OR (tam thuc)) va ((danh vai) or (doanh van)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach xa tang ha hoi. hieu ve ((tham thuc) OR (tam thuc)) va ((danh vai) OR (doanh van)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach xa tang ha hoi. hieu ve ((tham thuc) OR (tam thuc)) va ((danh vai) or (doanh van)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: su sach xa tang ha hoi. hieu ve ((tham thuc) OR (tam thuc)) va ((danh vai) or (doanh van)) cuu tre*.