Perhaps you should try some spelling variations:
thanh may » thanh tay, hanh may, thanh mau
duc tien » duc thien, luc tieng, thuc tien
va thanh » gia thanh, ban thanh, va tinh
duc tre » duoc tren
cac tuc » cac toc, cac tu, cac tac
tu sach » thu sach, su sach, tu cach
hieu ve » hieu va, hieu van
ky dang » ky nang, ky danh
te sach » toc sach
su hoa » su hoan, su hoat, su khoa
tuc va » thuc va, truc va, tuc xa
ve cac » va cac, vien cac

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 (te sach)) ky dang su hoa. hieu ve cac tuc va thanh may ((duc tre) OR (duc tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ky dang su hoa. hieu ve cac tuc va thanh may ((duc tre) OR (duc tien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) ky dang su hoa. hieu ve cac tuc va thanh may ((duc tre) OR (duc tien))".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) ky dang su hoa. hieu ve cac tuc va thanh may ((duc tre) OR (duc tien))*.