Perhaps you should try some spelling variations:
sach nang » cach mang, sach dung, sach danh
minh hai » minh khai, tinh hai, manh hai
sach nay » sach hay, sach vay, sach ngan
va triet » va thiet, va trien, ve triet
lang xa » lang ha, dang xay, lang van
va minh » van minh, vua minh, va kinh
va cam » va cham, va cac, va cao
xuc va » duc va, tuc va, luc va
hai va » hai van, thai va, hoi va
ve tai » te tai, de tai, le tai

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc ((sach nay) OR (sach nang)) lang xa hoi. hieu ((ve tai) or (va cam)) xuc va minh hai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc ((sach nay) OR (sach nang)) lang xa hoi. hieu ((ve tai) OR (va cam)) xuc va minh hai va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc ((sach nay) OR (sach nang)) lang xa hoi. hieu ((ve tai) or (va cam)) xuc va minh hai va triet".
• Adding a wildcard symbol may retrieve word variants: thuoc ((sach nay) OR (sach nang)) lang xa hoi. hieu ((ve tai) or (va cam)) xuc va minh hai va triet*.