Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
dau truc » cau truc, dai truc, doan truc
tu sach » su sach, te sach, tu cach
nang xa » lang xa, nang ma, mang xa
qua dau » qua da, qua bau, qua dan
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
tu tren » tu truyen, tu tieng, tu trong
vi tu » vi tut, voi tu, va tu

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) OR (thu sach)) ky ((nang xa) or (nang x)) hoi. hieu qua dau truc va hanh vi tu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky ((nang xa) OR (nang x)) hoi. hieu qua dau truc va hanh vi tu tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky ((nang xa) or (nang x)) hoi. hieu qua dau truc va hanh vi tu tren".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) ky ((nang xa) or (nang x)) hoi. hieu qua dau truc va hanh vi tu tren*.