Perhaps you should try some spelling variations:
trien thuat » thien thuat, trien hoat, chien thuat
nganh khong » nhanh chong, nganh nong, nganh khoa
nganh cong » nhanh chong, thanh cong
pho thong » he thong
ki thuat » ky thuat
tu sach » thu sach, su sach, tu cach
te sach » toc sach

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)) ((trien thuat) or (ki thuat)) ((nganh khong) or (nganh cong)) pho thong~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ((trien thuat) OR (ki thuat)) ((nganh khong) OR (nganh cong)) pho thong.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) ((trien thuat) or (ki thuat)) ((nganh khong) or (nganh cong)) pho thong*.