Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
pham thuc » phap thuc, pham chuc, pham thu
va doanh » van doanh, vay doanh, va danh
tu sach » thu sach, su sach, te sach
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
cuc tre » duc tre, cua tre, cuu tre
sach 2 » 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: tu sach 2 ((nang xa) or (lang xa)) hoi. hieu ve ((pham thuc) OR (nham thuc)) va doanh tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach 2 ((nang xa) OR (lang xa)) hoi. hieu ve ((pham thuc) OR (nham thuc)) va doanh tai cuc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach 2 ((nang xa) or (lang xa)) hoi. hieu ve ((pham thuc) OR (nham thuc)) va doanh tai cuc tre".
• Adding a wildcard symbol may retrieve word variants: tu sach 2 ((nang xa) or (lang xa)) hoi. hieu ve ((pham thuc) OR (nham thuc)) va doanh tai cuc tre*.