Perhaps you should try some spelling variations:
va nhanh » va thanh, va hanh, va nhan
tu sach » thu sach, su sach, te sach
cay chu » ca chu, cac chu, can chu
cay cuu » cap cuu, cham cuu
cac tuc » cac toc, cac tu, cac tac
nang xa » lang xa, nang ma, mang xa
qua cac » cua cac
tuc va » thuc va, truc va, tuc xa

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 y ((nang xa) or (nang x)) hoi. hieu qua cac tuc va nhanh ((cay cuu) OR (cay chu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (nang x)) hoi. hieu qua cac tuc va nhanh ((cay cuu) OR (cay chu)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((nang xa) or (nang x)) hoi. hieu qua cac tuc va nhanh ((cay cuu) OR (cay chu)) tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang xa) or (nang x)) hoi. hieu qua cac tuc va nhanh ((cay cuu) OR (cay chu)) tre*.