Perhaps you should try some spelling variations:
phap thuc » phap thu, phap hoc, phap tu
toc sach » hoc sach, doc sach, thuoc sach
su sach » so sach, vu sach
ve phap » va phap, de phap, ve phan
va danh » va dinh, va dan, va hanh
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cuu tre » cua tre, cau tren, cau treo
vi cuu » vi luu, vinh cuu
tinh » trinh, dinh, minh

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) or (toc sach)) ky lang xa hoi. hieu ve phap thuc ((may tinh) or (va danh)) vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (toc sach)) ky lang xa hoi. hieu ve phap thuc ((may tinh) OR (va danh)) vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (toc sach)) ky lang xa hoi. hieu ve phap thuc ((may tinh) or (va danh)) vi cuu tre*.