Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
thuc xay » thuc day, tuc xay, thuat xay
tu sach » thu sach, te sach, tu cach
han tri » han tai, van tri, thanh tri
xay han » xay chen, bay than, cay than
su pham » san pham
hieu su » hieu sau, tieu su, hieu so
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
su sach » so sach, vu sach
cua tu » cua tuc, cua su, cua cu

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 (su sach)) ky ((nang xa) OR (lang xa)) hoi. hieu su pham thuc xay han tri cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky ((nang xa) OR (lang xa)) hoi. hieu su pham thuc xay han tri cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky ((nang xa) OR (lang xa)) hoi. hieu su pham thuc xay han tri cua tu".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky ((nang xa) OR (lang xa)) hoi. hieu su pham thuc xay han tri cua tu*.